It can, and is, being done. I am in the process of finishing up my brakes this week or so.
I will end up with a frame mounted 7" dual diaphram booster and dual pot master cylinder feeding the original drum brakes on my '46 2 ton.
This will work for my truck, which should weigh in around 6500 lbs. I cannot speak for those who are actually using their truck as a true work horse. Mine is more of a hot rod.
