The problem with the HGP or “Game plan” hoppers is there are no parts available anymore, they went out of production about 1993. I’d personally change them over or convert them to a HSH Hopper which is the newer style, if the cabinet is in good condition. But it’s not going to be cheap. You’re going to have to replace the guts of the changer, Wiring harness, Hopper mounting plate, Hopper, and upgrade the software in the controller, if you’re using a v4.3 controller you’ll need to go to v5.3 software
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