Is catalyzed urethane ok for guitars?

Thanks so much for all the videos!!  I've learned so much from you while building my first guitar.  I had a quick question on clear coating.  My plan is to do the zpoxy thing over mahogany and tint the clear. I have some experience using PPG automotive clear and wondered if it's ok to use on a guitar or is it best to use a clear designed for  guitars?  I'm guessing the car stuff would dry faster?

Yep! Catalyzed urethanes are fantastic for this sort of thing. I use 'em, too. Shoot 2-3 coats of clear, sand flat with 600 grit the next day, and shoot about 3 more coats.