How to Attach a Guitar to a VRM Model Using Modular Avatar (Pivot at Waist, Pointing to Left Hand)

Hello, I’m a beginner with Unity. I just installed Unity yesterday and have been trying to figure out how to attach a guitar to a VRM model.

What I Want to Achieve:
I want to attach a guitar to a VRM model so that:

  • The waist acts as the pivot point
  • The guitar (FBX object) aligns its direction to the XYZ position of the left hand bone

What I’ve Tried:
Environment:

  • Installed VCC, UniVRM, and Modular Avatar

Settings Applied:
For the guitar FBX object, I have:

  • Added it as a child object with “Keep World Position” enabled in Modular Avatar
  • Used Modular Avatar’s “BoneReference” to assign the left hand bone

Problem:
With this setup, the guitar follows both the position and direction of the left hand, but I want it to only follow the direction while keeping the waist as the pivot.
I’m looking for a way to make the guitar rotate to match the left hand while keeping its position relative to the waist.

If anyone familiar with Modular Avatar or VRM has a good solution, I would really appreciate your help!
Thank you in advance!