I bought a brake booster from a 94 integra since it’s large than the civic’s stock one and provides better braking pressure. Along with this I also had to purchase a Brake Master Cylinder from a Integra GSR that didn’t have ABS since the car that I got the booster/suspension setup had it so the brake line setup was different and would not directly work with the civic.
The Brake Booster I picked up had brake fluid spill on it and eat up the paint. So I used a wire-wheel brush and some sand paper to clean up all the bad paint and some surface rust.
After that was cleaned off I used some blue painters tape to block the threaded studs, vacuum tube, top label, and the center plunger/hole.
After everything was tapped up I used some rubbing alcohol to clean up all the surfaces and used a Primer Paint combo spray paint can and gave 3 coatings, unfortunately i must have not sanded some spots perfectly because there was a few random small dots around the vacuum tube line that would not hold paint, but it came out good enough for my needs.
After the paint dried I attached the new brake master cylinder to the booster, although I had to re-use the old MC gasket as the new one was slightly too big for some reason (I suspect over 28 years it expanded a little as this was a new-part-old-stock) and after using the old gasket it mounted up perfect and this was the end result: