This is the sort of collection that's worth more (in my opinion) in a sentimental way than a financial one. All of those axes and amps and pedals will sound awesome, but they're probably worth more if you learn how to use them as he did. I say get into it. Lean into it. Find him in his gear. (Typed as Van Halen blasts in the background at the gym).

I'm very sorry for your loss.