diff --git a/lightclient-circuits/src/committee_update_circuit.rs b/lightclient-circuits/src/committee_update_circuit.rs
index 956cd59..08d720d 100644
--- a/lightclient-circuits/src/committee_update_circuit.rs
+++ b/lightclient-circuits/src/committee_update_circuit.rs
@@ -90,7 +90,7 @@ impl<S: Spec, F: Field> CommitteeUpdateCircuit<S, F> {
             .hash_tree_root()
             .unwrap()
             .as_ref()
-            .into_iter()
+            .iter()
             .map(|v| builder.main().load_witness(F::from(*v as u64)))
             .collect_vec();
         verify_merkle_multiproof(
diff --git a/lightclient-circuits/src/sync_step_circuit.rs b/lightclient-circuits/src/sync_step_circuit.rs
index 45880b3..c230358 100644
--- a/lightclient-circuits/src/sync_step_circuit.rs
+++ b/lightclient-circuits/src/sync_step_circuit.rs
@@ -121,7 +121,7 @@ impl<S: Spec, F: Field> StepCircuit<S, F> {
             .hash_tree_root()
             .unwrap()
             .as_ref()
-            .into_iter()
+            .iter()
             .map(|v| builder.main().load_witness(F::from(*v as u64)))
             .collect_vec();
 
@@ -156,7 +156,7 @@ impl<S: Spec, F: Field> StepCircuit<S, F> {
             .hash_tree_root()
             .unwrap()
             .as_ref()
-            .into_iter()
+            .iter()
             .map(|v| builder.main().load_witness(F::from(*v as u64)))
             .collect_vec();
 
diff --git a/lightclient-circuits/src/witness/multiproof.rs b/lightclient-circuits/src/witness/multiproof.rs
index 7d41a6c..968b2ca 100644
--- a/lightclient-circuits/src/witness/multiproof.rs
+++ b/lightclient-circuits/src/witness/multiproof.rs
@@ -198,3 +198,19 @@ pub fn block_header_to_leaves(
         header.body_root.hash_tree_root()?,
     ])
 }
+
+pub fn beacon_header_multiproof_and_helper_indices(
+    header: &mut BeaconBlockHeader,
+    gindices: &[usize],
+) -> (Vec<Node>, Vec<usize>) {
+    let header_leaves = block_header_to_leaves(header).unwrap();
+    let merkle_tree = merkle_tree(&header_leaves);
+    let helper_indices = get_helper_indices(gindices);
+    let proof = helper_indices
+        .iter()
+        .copied()
+        .map(|i| merkle_tree[i])
+        .collect::<Vec<_>>();
+    assert_eq!(proof.len(), helper_indices.len());
+    (proof, helper_indices)
+}
diff --git a/preprocessor/src/rotation.rs b/preprocessor/src/rotation.rs
index 6684b9d..6bb543f 100644
--- a/preprocessor/src/rotation.rs
+++ b/preprocessor/src/rotation.rs
@@ -6,10 +6,10 @@ use std::marker::PhantomData;
 
 use beacon_api_client::{BlockId, Client, ClientTypes};
 use eth_types::Spec;
-use ethereum_consensus_types::{BeaconBlockHeader, LightClientUpdateCapella};
+use ethereum_consensus_types::LightClientUpdateCapella;
 use itertools::Itertools;
 use lightclient_circuits::witness::{
-    block_header_to_leaves, get_helper_indices, merkle_tree, CommitteeUpdateArgs,
+    beacon_header_multiproof_and_helper_indices, CommitteeUpdateArgs,
 };
 use log::debug;
 use ssz_rs::Merkleized;
@@ -95,20 +95,6 @@ where
         "Execution payload merkle proof verification failed"
     );
 
-    let beacon_header_multiproof_and_helper_indices =
-        |header: &mut BeaconBlockHeader, gindices: &[usize]| {
-            let header_leaves = block_header_to_leaves(header).unwrap();
-            let merkle_tree = merkle_tree(&header_leaves);
-            let helper_indices = get_helper_indices(gindices);
-            let proof = helper_indices
-                .iter()
-                .copied()
-                .map(|i| merkle_tree[i])
-                .collect_vec();
-            assert_eq!(proof.len(), helper_indices.len());
-            (proof, helper_indices)
-        };
-
     let (finalized_header_multiproof, finalized_header_helper_indices) =
         beacon_header_multiproof_and_helper_indices(
             &mut update.finalized_header.beacon.clone(),
diff --git a/preprocessor/src/step.rs b/preprocessor/src/step.rs
index 3c1b98f..ca2cd75 100644
--- a/preprocessor/src/step.rs
+++ b/preprocessor/src/step.rs
@@ -9,13 +9,9 @@ use beacon_api_client::{BlockId, ClientTypes, StateId};
 use eth_types::Spec;
 use ethereum_consensus_types::bls::BlsPublicKey;
 use ethereum_consensus_types::signing::{compute_domain, DomainType};
-use ethereum_consensus_types::{
-    BeaconBlockHeader, ForkData, LightClientBootstrap, LightClientFinalityUpdate,
-};
+use ethereum_consensus_types::{ForkData, LightClientBootstrap, LightClientFinalityUpdate};
 use itertools::Itertools;
-use lightclient_circuits::witness::{
-    block_header_to_leaves, get_helper_indices, merkle_tree, SyncStepArgs,
-};
+use lightclient_circuits::witness::{beacon_header_multiproof_and_helper_indices, SyncStepArgs};
 use ssz_rs::Vector;
 use ssz_rs::{Merkleized, Node};
 
@@ -123,21 +119,6 @@ pub async fn step_args_from_finality_update<S: Spec>(
         "Finality merkle proof verification failed"
     );
 
-    let beacon_header_multiproof_and_helper_indices =
-        |header: &mut BeaconBlockHeader, gindices: &[usize]| {
-            let header_leaves = block_header_to_leaves(header).unwrap();
-            let merkle_tree = merkle_tree(&header_leaves);
-            let helper_indices = get_helper_indices(gindices);
-            let proof = helper_indices
-                .iter()
-                .copied()
-                .map(|i| merkle_tree[i])
-                .collect_vec();
-            // println!("Proof length: {}", proof.len());
-            assert_eq!(proof.len(), helper_indices.len());
-            (proof, helper_indices)
-        };
-
     // Proof length is 3
     let (attested_header_multiproof, attested_header_helper_indices) =
         beacon_header_multiproof_and_helper_indices(
diff --git a/preprocessor/src/unit_test_gen.rs b/preprocessor/src/unit_test_gen.rs
index 15d56a5..42d88e4 100644
--- a/preprocessor/src/unit_test_gen.rs
+++ b/preprocessor/src/unit_test_gen.rs
@@ -9,8 +9,8 @@ use ethereum_consensus::signing::compute_signing_root;
 use ethereum_consensus::state_transition::Context;
 use itertools::Itertools as _;
 use lightclient_circuits::witness::{
-    block_header_to_leaves, get_helper_indices, merkle_tree, parent, CommitteeUpdateArgs,
-    SyncStepArgs,
+    beacon_header_multiproof_and_helper_indices, get_helper_indices, merkle_tree, parent,
+    CommitteeUpdateArgs, SyncStepArgs,
 };
 use ssz_rs::{MerkleizationError, Merkleized, Node};
 use std::fs::File;
@@ -156,20 +156,6 @@ fn main() {
         body_root: finalized_block.body_root,
     };
 
-    let beacon_header_multiproof_and_helper_indices =
-        |header: &mut ethereum_consensus_types::BeaconBlockHeader, gindices: &[usize]| {
-            let header_leaves = block_header_to_leaves(header).unwrap();
-            let merkle_tree = merkle_tree(&header_leaves);
-            let helper_indices = get_helper_indices(gindices);
-            let proof = helper_indices
-                .iter()
-                .copied()
-                .map(|i| merkle_tree[i])
-                .collect_vec();
-            assert_eq!(proof.len(), helper_indices.len());
-            (proof, helper_indices)
-        };
-
     // Proof length is 3
     let (attested_header_multiproof, attested_header_helper_indices) =
         beacon_header_multiproof_and_helper_indices(
diff --git a/test-utils/src/lib.rs b/test-utils/src/lib.rs
index 8d45ec2..1252a45 100644
--- a/test-utils/src/lib.rs
+++ b/test-utils/src/lib.rs
@@ -20,7 +20,7 @@ use ethereum_consensus_types::{ForkData, Root};
 use itertools::Itertools;
 use lightclient_circuits::poseidon::poseidon_committee_commitment_from_uncompressed;
 use lightclient_circuits::witness::{
-    block_header_to_leaves, get_helper_indices, merkle_tree, CommitteeUpdateArgs, SyncStepArgs,
+    beacon_header_multiproof_and_helper_indices, CommitteeUpdateArgs, SyncStepArgs,
 };
 use ssz_rs::prelude::*;
 use ssz_rs::Merkleized;
@@ -114,21 +114,6 @@ pub fn read_test_files_and_gen_witness(
     let mut agg_pk: ByteVector<48> = ByteVector(Vector::try_from(agg_pubkeys_compressed).unwrap());
 
     sync_committee_branch.insert(0, agg_pk.hash_tree_root().unwrap().deref().to_vec());
-
-    let beacon_header_multiproof_and_helper_indices =
-        |header: &mut BeaconBlockHeader, gindices: &[usize]| {
-            let header_leaves = block_header_to_leaves(header).unwrap();
-            let merkle_tree = merkle_tree(&header_leaves);
-            let helper_indices = get_helper_indices(gindices);
-            let proof = helper_indices
-                .iter()
-                .copied()
-                .map(|i| merkle_tree[i])
-                .collect_vec();
-            assert_eq!(proof.len(), helper_indices.len());
-            (proof, helper_indices)
-        };
-
     let (finalized_header_multiproof, finalized_header_helper_indices) =
         beacon_header_multiproof_and_helper_indices(
             &mut sync_wit.attested_header.clone(),
@@ -271,20 +256,6 @@ fn to_sync_ciruit_witness<const SYNC_COMMITTEE_SIZE: usize>(
         .map(|b| b.deref().to_vec())
         .collect();
 
-    let beacon_header_multiproof_and_helper_indices =
-        |header: &mut BeaconBlockHeader, gindices: &[usize]| {
-            let header_leaves = block_header_to_leaves(header).unwrap();
-            let merkle_tree = merkle_tree(&header_leaves);
-            let helper_indices = get_helper_indices(gindices);
-            let proof = helper_indices
-                .iter()
-                .copied()
-                .map(|i| merkle_tree[i])
-                .collect_vec();
-            assert_eq!(proof.len(), helper_indices.len());
-            (proof, helper_indices)
-        };
-
     // Proof length is 3
     let (attested_header_multiproof, attested_header_helper_indices) =
         beacon_header_multiproof_and_helper_indices(