I bought the trunk eddy replacement board and asked Martin why the size was larger. He said, quite logically, that they designed it once for multiple machines. I'm not sure which was the original it was designed to replace. If there were more of a market for the boards, they could justify multiple designs. While I wasn't crazy about putting new holes on the bottom of the playfield it really did work out just fine. It works great and I don't have to pull the glass and adjust every other day anymore.