Salty (on the H.A.M.B.) is doing some major updates to his 1950 Chevy pickup truck, and documenting it all in this thread.  He called a little while ago and asked if we could come up with a solution to mount his booster under the floor, but his frame was very narrow.  Here’s a photo of what we came up with:

You can see how he brought the booster bracket up over the top of the frame rail until the booster was very close the the inside of the rail.  He did the same thing to the pedal bracket – the bent plate actually sandwiches the pedal against the inside of the frame rail… you can’t get much tighter than that!