[Mike C]

Heat rejection is about mass, and the 12” truck rotors that are 1 1/4” wide have excellent heat rejection. They also have the 5x5 bolt pattern for truck wheels to bolt up to. They were designed for a truck and balanced for the truck. The stock brakes were good enough the only change GM made to them from 71-91 was to. Make the rotor have LESS mass on some later trucks. GM considered them to be sufficient for Suburbans that weighed 1000# more than a truck.

Spend some $$$ on good brake pads and if your rotors are close to minimum spec get some new ones. Otherwise get them turned for your new pads. Work at making sure system is bled, and as mentioned above, a compliant but firm suspension and sticky tires really take it to the next level. If you want it to feel more powerful and you have manual discs, the power booster will help with that.

And when you need to service it, factory 71-72 parts can be used for the brakes without having to figure out what all parts have been combined for a different solution.