Help with selecting gltf parts

Questions
1

I need help selecting parts of a gltf model to recolor but it does not have a name, in blender the only thing it has is “Mesh_12” please help

2 
let meshes=[]
let object = gltf.scene.getObjectByName("Mesh_12");
//If object isn't a Mesh here (i.e. doesn't have a .material) then it might be deeper
//so you can:
object.traverse(e=>e.isMesh && meshes.push(e)); //To get any meshes on or under this node.

//now meshes will contain all the meshes under the object found by name.