Are you running v6 calipers?
The MC on my first gen went bad so I replaced it with a 1'' bore MC. I didnt change anything else and now the pedal is very hard and I have to stand on it. I Assume the entire system needs to be swapped over. It looks like the only option for an upgraded booster in a first gen is a 22ret booster and they are about $200, I'm gonna go back to a stock MC for now.
