Here’s a DIY I made. Same procedure would be used but with a drum/drum master cylinder. I have this same setup on 2 trucks. Works great and affordable. One thing I don’t mention in the DIY is that the little rod sticking out of the front of the booster needs to be properly adjusted. If adjusted too long, it will prevent the MC plunger from returning to the home position. Happened to me.
The booster I show in the DIY will allow you to keep a factory air cleaner on an inline 230ci or 250ci.
DIY Brake booster
