Maybe he is referring to the A500 and the external left expansion port the ACAs use.
If you have an A500 there are internal ones:
http://kipper2k.com/accel500.html
EDIT: Ups... Sorry I see now the title of the thread
So yes, all of the A1200 accelerator use the bottom expansion slot:
http://amigakit.leamancomputing.com/...oducts_id=1002