Having done several disc brake conversions I have to caution you on over generalizing what will interchange with another kit.
I have seen older disc brake kits that use the stock hubs and late 70's 6 lug truck rotors. I have installed kits that use a one piece 6 lug 11" rotor and another that uses a 6 lug 12" one piece rotor. I installed a 5 lug kit on my 56 that uses 11" rotors and calipers from a mid 70's Malibu/Camaro. I have disc brakes on my 57 car that use components from a 72 Chevelle. All of these have different offsets and use different brackets. Some of them use the same calipers, some do not. There are numerous aftermarket suppliers that use similar parts in their kits but if you try to mix and match you could easily end up with a whole bunch of stuff that doesn't work.
Fred


1956 3100 Pickup/Red/350/3sp OD/PS/Disc Brakes
1957 Bel Air Sport Coupe/Red/355/TH350/PS/Disc Brakes
2017 Silverado LT Single Cab SB/Black/5.3/6 Speed Trans
1947 Willys CJ2A w/F-Head engine