Shaderworks has a utility for changing materials very easily:-

I'll drop you a PM as I don't think we can post a link to paid for products here.

I will say it does make things a lot easier.

The other ones I use all the time are MATWriter Panel and Thumbnail Designer by Netherworks.

All the best.

Great Uncle LROG

Who honors those we love for the very life we live?, Who sends monsters to kill us?, and at the same time sings that we will never die., Who teaches us whats real?, and how to laugh at lies?, Who decides why we live and what we'll die to defend?, Who chains us?, and Who holds the key that can set us free... It's You!, You have all the weapons you need., Now Fight!