? about brakes

[arkracing]

can i put a 73+ master cylinder/prop. valve on an aftermarket booster made for 67-72 trucks (basically a conversion booster)??????

or do i have to use 72 master/valve?

i'm only curious because the front disc brakes are the same from '72-'78 (then '78+ as long as they are 1+1/4" Rotors) so i can't see why a 73+ master/valve wouldn't work (at least ECE "dosen't recommend doing it")

and if i have to use the '72 master could i use a 73+ prop.??? cause i really don't feel like spending another $100 for a master+prop.valve for this thing and i have a '73 prop. valve

i just don't understand why they wouldn't recommend it if the brakes fit 72-78 trucks?