It can be done. I see the name Hydrovac mentioned on Stovebolt quite a bit for the 46-53 Chevy trucks. I had a 63 that the previous owner had installed a power brake booster on top of the frame under the master cylinder, no reason it couldn't have been under the cab. The unit was non-op when I got the truck. I ended up selling it to Power Brake Exchange in San jose, was surprise at the core value.
Larry
