Any chance of redesigning the Prom in a way that it would fit easier/better ? Or maybe some minimalist Zorro3-busboard with one slot (oriented in a way to make the Prom sit where it should sit).
Or maybe a Zorro right-angle adaptor? Better yet, add that to a small PCB to reposition the card so it obscures the ISA slots - almost no one uses those these days - while keeping Zorro slots free.
