Script to override SteamVR controller textures on load. Modified from »Mr_FJ« https://steamcommunity.com/app/358720/discussions/0/357287304420388604/

OverrideControllerTexture.cs

using UnityEngine;
using System.Collections;

/// <summary>
/// Override the texture of each of the parts with your texture.
/// </summary>
public class OverrideControllerTexture : MonoBehaviour
{
    #region Public variables
    [Header("Variables")]
    public Texture2D albedoTexture;
    public Texture2D normalTexture;
    public Texture2D metallicTexture;
    public Texture2D specularTexture;
    #endregion

    void OnEnable()
    {
        //Subscribe to the event that is called by SteamVR_RenderModel, when the controller mesh + texture has been loaded completely.
        SteamVR_Events.RenderModelLoaded.Listen(OnControllerLoaded);
    }

    private void OnDisable()
    {
        //Unsubscribe from the event if this object is disabled.
        SteamVR_Events.RenderModelLoaded.Remove(OnControllerLoaded);
    }

    public void UpdateControllerTexture(Texture2D newTexture, Transform modelTransform)
    {
        // store all controller materials
        var materials = new ArrayList
        {
            modelTransform.Find("body").GetComponent<MeshRenderer>().material,
            modelTransform.Find("button").GetComponent<MeshRenderer>().material,
            modelTransform.Find("led").GetComponent<MeshRenderer>().material,
            modelTransform.Find("lgrip").GetComponent<MeshRenderer>().material,
            modelTransform.Find("rgrip").GetComponent<MeshRenderer>().material,
            modelTransform.Find("scroll_wheel").GetComponent<MeshRenderer>().material,
            modelTransform.Find("sys_button").GetComponent<MeshRenderer>().material,
            modelTransform.Find("trackpad").GetComponent<MeshRenderer>().material,
            modelTransform.Find("trackpad_scroll_cut").GetComponent<MeshRenderer>().material,
            modelTransform.Find("trackpad_touch").GetComponent<MeshRenderer>().material,
            modelTransform.Find("trigger").GetComponent<MeshRenderer>().material
        };

        // give the materials textures
        foreach (Material m in materials)
        {
            //convert to valve shader
            m.shader = Shader.Find("Valve/vr_standard");

            m.SetInt("_SpecularMode", 1);
            m.DisableKeyword("S_SPECULAR_NONE");
            m.DisableKeyword("S_SPECULAR_METALLIC");
            m.EnableKeyword("S_SPECULAR_BLINNPHONG");

            // set main, normal and metallic textures
            m.mainTexture = newTexture;
            m.SetTexture("_BumpMap", normalTexture);
            m.EnableKeyword("_NORMALMAP");
            m.SetTexture("_SpecGlossMap", specularTexture);
            m.EnableKeyword("_SPECGLOSSMAP");

            m.SetFloat("g_flReflectanceMax", 0.5f); // max reflectance

            // convert to metallic
            //            m.SetInt("_SpecularMode", 2);
            //            m.DisableKeyword("S_SPECULAR_NONE");
            //            m.DisableKeyword("S_SPECULAR_BLINNPHONG");
            //            m.EnableKeyword("S_SPECULAR_METALLIC");
            //            m.SetTexture("_MetallicGlossMap", metallicTexture);
            //            m.EnableKeyword("_METALLICGLOSSMAP");
        }

        // dim the less important elements (optional)
        ((Material)materials[0]).SetFloat("g_flCubeMapScalar", 0.1f); // body
        ((Material)materials[6]).SetFloat("g_flCubeMapScalar", 0.1f); // system btn
        ((Material)materials[7]).SetFloat("g_flCubeMapScalar", 0.1f); // trackpad
        ((Material)materials[8]).SetFloat("g_flCubeMapScalar", 0.1f); // trackpad
    }

    /// <summary>
    /// Call this method when the RenderModelLoaded event is triggered.
    /// </summary>
    /// <param name="args">SteamVR_RenderModel renderModel, bool success</param>
    void OnControllerLoaded(SteamVR_RenderModel renderModel, bool success)
    {
        if (!success) return;
        UpdateControllerTexture(albedoTexture, renderModel.gameObject.transform);
    }
}

Hey thanks for making this to let you know I had to comment out
m.shader = Shader.Find("Valve/vr_standard");

        m.SetInt("_SpecularMode", 1);
        m.DisableKeyword("S_SPECULAR_NONE");
        m.DisableKeyword("S_SPECULAR_METALLIC");
        m.EnableKeyword("S_SPECULAR_BLINNPHONG");

to make it work. Before it would only come up pink as it was missing a shader.

Thanks again,
Mitch