I just did this job in two of my cars a few weeks ago. There are #4 nuts to remove up under the dash, and one bolt from the engine compartment side. BUT, on one of the cars, the stud had 2(
) nuts on it--one that held on (also) a brace to the lower dash, and beneath that was the "real" nut holding the booster in. This was a car that had never been touched, and it was the second job that I did. I also couldn't figure out why the booster was loose-ish, but wouldn't come right out. Once I got the "hidden" nut off, the booster was not stuck on, it come right off. I can post a picture if you need it, but it was a stud to the gas pedal side of the booster, and not the top one. Good luck.
