I just did this on 55 2nd 3/4 ton. Do search on 55 2nd 3/4 ton dual master. I replaced all line, master, slaves, pads, springs everything. The master came from Classic Performance Products and includes the adapter bracket, everything else came from the local auto parts store. I recommend new over rebuilt master and slaves, mine were at least 20 years old and were to far gone. I had two issues, I needed a longer push rod from pedal to master piston than was supplied with the kit, and you need to adjust the brake pads as per the manual prior to final bleed. Bench bleed master, bleed longest lines first then shortest on front and rear respectively [separate reservoirs] and then adjust brake pads per manual. This is critical. Then do final bleed.
good luck
