No reason to use anyone but
@DoctorDiff if you're going 5x4.5". Best customer service out there, and great products. The rear disk kit he sells also allows for the use of the original tapered style axle bearings, a lot of kits out there need the green bearings to work.
DoctorDiff Drivetrain Components
I wouldn't use a 1.125" master cylinder either. If you're going to use a power disk set up it might be ok, but the stock 1 1/32" would be better. And if you're going to be using manual disks then 15/16" is the way to go. Doctor diff sells a very nice master cylinder as well. For a 4 wheel disk set up you should use an adjustable prop valve to get the rears dialed in correctly. Some have managed without one, but there's a lot of variables and the only way to really be sure is to use an adjustable.
