I was originally planning to use two machine-pin headers to connect the adapter board to the cartridge board. Then I found this neat part at DigiKey and I decided it would be nice to use one of those instead. I got one, and after removing the old FeRAM chip, I found that the new socket is too tall to fit in the cartridge. I also found that with the thickness of the new FeRAM chip stacked on top of a 1.6 mm PCB seated on that socket, the cartridge will have no hope whatsoever of being assembled. Heck, I'd probably have to cut a hole in the front for the new FeRAM chip to stick out through. It should be needless to say that this would be unacceptable, so I won't bother saying it.

What to do then? I looked at the original board, checked some thicknesses, and got an idea. Just put a piece of Kapton tape where the new board will go (merely for paranoia, probably not needed) and connect the two PCBs together with short pieces of bare 22 AWG wire. The whole assembly will be around the original thickness, or maybe even a little less. Everything will probably work out fine.