The booster also uses a different pattern to bolt to the firewall. And the master cylinder bolt patterns are different >.<

 

Then probably the best idea will be the proportional valve. Remember we are all amateurs just like you. The best way to get a good answer would be to check with a brake shop. Someone who really knows brakes, not just a grease monkey.

 

I decided hell with it. We just bought new drums, 1 ton cylinders, and some new shoes. Came out like 130 cheaper than the rear end without counting a 40 dollar proportioning valve. My dad just threw some paint on the drums to match the front calipers. I'll post some pics soon. Also going to end up painting the rear end, leaf springs, etc this weekend when we modify the shackles and hangers to drop it.