[Chuck78]

I saw this thread and was interested as I have had an 89 Suburban 1/2 ton disc brake front crossmember in the garage for a decade now, awaiting me getting settled into my life with enough time to perform the swap. I have already dealt with the hydraulic clutch setup a decade ago before I got sidetracked with life.
I added a small diameter but thicker power booster from Pirate Jack's I believe it was, used a 67 1 ton master cylinder as it had what I then calculated as the correct bores for a rear drum/front disc setup once removing the front proportioning valve from the master (turned out my slight initial fears were worse, this was calculated for front disc fluid leverage ratios, and gives the rear far too much power if still 4 wheel drum, 45mph panic stop locked up the rears to avoid crushing an idiot that cut me off doing 10mph & I slid sideways through a road sign post...).
I used I believe a standard mechanical clutch gmc brake master cylinder for the clutch (memory is foggy here, search the old archived Yahoo posts for my info under Chuck or Chuck78). Finding an appropriate clutch line to replace mine was the most difficult part, but a hydraulic shop custom line would be simple.
I fabbed up my own power booster bracket to space the booster in front of the clutch master. I used what I recall being two different power booster brackets MIG welded together in the middle to give me the extra distance, & the pedal to booster rod was a piece ir two that I assembled from parts from Pirate Jack's catalog.

I wish I could find my fresh install pics. I'll snap a pic of 10+ years later, nice rusty master cylinders from sitting outside...