Originally Posted by david-b
I was going through that same list and they're all close, but all different at the same time. The booster I have has the 4 studs in the same position as the stock on, but just need that adapter to have the right pattern on the firewall. I tried to get the stock one off, with no luck though. Is there a trick? It's the original booster that I pulled off, and everything is rusted into one piece.
You might have to separate the vacuum chamber to access the inside back half of the booster to see what the bracket is held on with if there's no obvious fasteners seen on the outside. I have never done this- so I'm shooting from the hip here.