[79vette]

Is there anything wrong with the existing brake system? I have a 77 K5 on 31s and an 86 K5 on 33s, and both will lock up the tires on dry pavement. 77 is a 350 with vacuum brakes and the 86 is a diesel with factory hydroboost.

What brake performance are you looking to add, specifically? As other posters have stated if you want better pedal feel discs and hydroboost could help with that. If you're racing or towing heavy and are getting brake fade you might need some upgraded parts, but both of those seem unlikely in a K10.

For what it's worth, I can't see needing fancy brakes on a half ton outside of those applications and I feel like the money could be better spent on engine, trans, suspension, steering, or interior upgrades and give much better bang for the buck. But it's your truck.