Just an update on the brake issue:
04/04/2009:
We just went back with the stock system. All new (non power)master cylinder, all wheel cylinders new, all new rubber lines, all new brake hardware & springs, and new rear brake shoes. ( The front shoes were nearly brand new. Evedently, my late great uncle replaced the front brake shoes just before he passed away 13 years ago.) This truck has not been driven more than 500 miles in the last 13 years. But for the first 30 years of it's life, the manual brakes worked just fine. So we figured it would be ok to just rebuild the factory system.