I have a 73 econoline box van I use for plumbing, the 4 wheel drums have been a major problem. I bought the best shoes,drums and new everything and it didn't stop worth a crap.
An old timer mechanic told me try some cheap or OEM shoes that are a softer material than my ceramic raybestos super duper expensive shoes and I'll be damned the thing stops on a dime now, I couldn't believe it! All the money I spent on new M/C,booster,wheel cyls,drums,shoes, mechanic after mechanic and all I did was buy organic cheap shoes and it solved my problem.
Same with my 2000 f-150, I bought the best pads they sell and they wore out quick but even worse warped my rotors in a month, then the same guy said buy factory ford pads they work the best and once again he was right.
\Some old tech stuff just wasn't made to work with new tech stuff and when you think you are upgrading you are making it worse.
I.E. take a ford 4100 carb then bolt on a 600 holley 1850 the4 4100 will excell everywhere over the modern one.
I know your year of truck came with front disc's as an option go get all the parts at a pick a part even junk stuff and use them as cores to get rebuilt or new stuff.
But on the cheap try some cheap organic shoes you will be surprised.
my 67 vert http://htwheelz.smugmug.com