get as much bad, worn, and old components out of your brake system as possible, if you are doing just one cylinder, i would replace them all if feasible. also, pads, rubber lines and anything and everything that can be replaced on the brake systems i would replace or at least look at very carefully. im going through all that now on mine and its well worth the time inspecting everything. the pedal only has to go to the floor once to cause an accident.
besides that, the brakes on these trucks are very easy to work on, you should have no problems if you have ever done any brake before