This question gets asked every day it seems lol. You will need a Disc/Drum M/C you should b able to keep your stock booster A lot of guys went with the Scarebird kit that will allow you to keep your stock Knuckles, Or you could find a 69-72 Disc brake Setup C-bodie but what you really want is a 73 C-Bodie Disc setup but those are getting harder to find. I would go with the Scarebird set up uses Cheap, Easy parts you can get anywhere, The people I have talked to that have done it are all happy with it.