I have a 1966 Chevelle that I've upgraded from front drum to power disc brakes from a 1972 Chevelle. What do I gain, if anything, if I upgrade to power disc brakes from a 90's-00's LSX Camaro, Firebird, Caprice, Corvette

, etc? I've also upgraded to quick ratio power steering, so that upgrade may be out. I considering a LSX engine and trans swap, so I'm deciding if to buy the whole car and use the front and rear suspension as well as the engine and trans. Thanks for any info.
JC