The booster would hook right up to the master under the floor. I looked at a 1947 Chevy's engine compartment just now on carnut.com and there was somthing that may have been a master cyl but looked diffrent. It had a Chevy Small block. Your easiest and best bet is to leave it under the floor, it will save you money because you would need to buy new pedal assemblies. You may need some kind of kit to convert it to a firewall master IF it is possible.