Quoted from songofsixpence:
Good to know!
So... pull the small transformer and associated rectifiers / fuses, and install a switching power supply. Would work on any game with Futaba-style replacement displays. Not a bad mod, if the value justifies the price.
I just did a quick write-up for it here:
I think I would just desolder the wires on the transformer and cap off the wires. Then, put the arcade power supply in the cabinet, and tap the incoming AC from the inner facing side of the EMI filter. Get an edge connector for J1 on the MPU, then run the 5v, 12v, and ground wires from the power supply to the J1 connector for the MPU.
So, if someone ends up finding an original transformer, they can easily reverse the modification and install a proper transformer.
: Actually, after glancing at the schematics, since the main fuse is after the EMI filter, you should tap somewhere else down the line after the fuse and power switch. You could probably put some ring terminals on the hot and common wires for the small transformer, and attach those to the arcade power supply. Then run a ground wire from the power supply to the ground terminal on the EMI filter.