I remember I attached an A2630 accelerator about ten years ago to an A500. It worked. Two things are important: double checking conections and keeping cables as short as possible, to avoid signal degradation.
I cant remember the exact way i did the wiring, but i did it by looking to the Amiga Hardware Reference Manual, and that was basically it.
Before you attempt a hack like this one i recomend you get yourself a proper card edge conector/cpu slot, both available in ebay from time to time at about 10 USD each.
Think about fixing the accelerator board in a specififc place and not moving it, or you will end up unsoldering your wiring.
Good Luck and happy hacking!
