I have a Game Plan Old Coney Island! that I have replaced the power board (PSU-1) with one from Gulf Pinball, who seems to be making a lot of replacement boards lately. Anyway, I also have an original power board (both are all installed to a transformer), and I've noticed some differences between them. The transformer assemblies were taken from 2 different machines (obviously), and thus it could be that they had different pin wiring - IOW, the board that is the "original one" might or might not be the one that was actually installed in the current cabinet. (The other cabinet is not available for inspection.)
 The Gulf Pinball board has the 680Ω resistor as dead (i.e., only one side is connected to anything, with the other side free), while the original board has this free side connected to ground. There is also a wire connect hole at this free side, but the directions that came with the board don't direct for any line to be connected there. And looking at the schematic that I have found online, this resistor doesn't even seem to exist.
 The Gulf Pinball board has the J5 connector (15-pin) key location as upside down relative to the original board - i.e., the key for the original board has the key at pin position #11 from the top while the Gulf Pinball board has the key as position 5 from the top, which corresponds to being pin position #11 from the bottom). However, the leads all match if referenced to the vertical positioning, and the actual cabinet wiring matches the original board (i.e., the leads relative to the key are the same for the original board and cabinet harness) - and this all matches the schematic. Thus, it would appear that the Gulf Pinball board has been done wrong. Indeed, the marking on the Gulf Pinball board shows the key as being position #5 from the top (there is no marking as to what is index 1), which matches where the key is. It seems to be as though the design for the Gulf Pinball board is such that it has been decided to make the key #5 instead of #11 (i.e, using the vertical positioning as the reference).
 There is also a difference in the wiring such that on the schematic & original board have the node (call it NODE A) from the 6.3V fuse (opposite the line from the transformer) going to pin position #2-4 and the ground going to pin position #6-8 - while the Gulf Pinball board has NODE A going to pin position #6-8.
So my first question is to anyone that has used this board, and has figured out what the deal is. The second question is what is the E-mail address of Gulf, as I would like to ask them about it.
The solution for  could be as easy as simply adding a jumper, with this extra jumper being part of the design. Perhaps it is not needed.
However, the solution for  - if it is to be such that either transformer assembly could be used as "plug & play" - is not apparent, although as the schematic & original board have pin position #5 as dead, and the cabinet has pin position #10 as dead, pins #5 & #10 could be clipped for it to fit.
The solution for  could only be that it makes no difference.
In general, I could buy the idea that  &  are valid designs, but I can't figure out how  is not a design error. Surely, there must be someone here who has used this replacement board.