Here is what I have checked so far and what I have found. First, when I am in test mode, and manually testing the solenoids, for flashers 1, 2, and 8 the test clicks once with no flash and then stops (no noise or flash). For all the other solenoid flash tests (where the flash works) the flash keeps on flashing until I manually advance the test). Not sure if that is significant or not, but I thought I would mention it.
I then checked the resistors in the Interconnect Board for continuity and all work EXCEPT R8. Not sure what R8 is for, but again, wanted to point this out.
With regard to wiring in the backbox, all wiring on the CPU Board (5) that I could tell relate to the flashers (i.e. 5J5 and 5J11) seems fine/matches the manual (5J5 had two black wires that looped around but were connected to the connector where the manual indicated - if a photo would be helpful I can attach one). On the Interconnect Board, 2J4, 2J7, and 2J12 all match the manual. For 2J8-3 my game is missing the violet wire indicated in the manual. Also, my 2J9 doesn't match the manual at all, as my wires are 2J9-1 YELLOW, 2J9-5 ORANGE, 2J9-6 BLUE, and 2J9-7 BROWN. Not sure if 2J9 would have any impact on the flashers (manual says this connector is for playfield general illumination), but again, thought I would mention it.
I haven't gotten under the playfield yet to follow the wires from the backbox to the flashers (although I have checked the wires at the flashers and they appear fine). Not sure if I will be able to do so today. Want to check continuity of the wire from the connectors in the backbox to where they end at the flasher bulb sockets. Not sure if there are other tests that I can run.