ufopinball , thanks, I’ll check that. The wire was definitely broken, but so where a lot of other things on this machine. Do you know what the c side power ac relay is and where? I see it’s in that column but I have no idea what it is.
Is That the interconnect?

Time for an update.. pictures to follow.

All the electronics are done, the playfield is repopulated and everything appears to be working on the bench.
I ended up getting a replacement mainboard from @dumbass. His work is excellent and service is phenomenal. If there were more people like him , the world would be a better place.

Lessons learned:

• Things may fit upside down or backwards, but that doesn't mean that they will work. (I had a few things I needed to fix)
• Have extra slow blow fuses on hand (I went through at least 1/2 dozen during this rebuild). Best one on this is that the metal from the rotisserie was causing a short on a couple of the upper general illumination (GI) lamps. That took 3 fuses alone to figure out.
• Sometimes you forget to install a nut on the playfield, or there is a long reach for the locknut. While I'm sure many of you already know this trick, I used a long screw to thread a couple of turns through the backside of the nut and used that as a way to reach and place the nut where we needed it.
• Sometimes it's easier to remove a few parts to install what you forgot rather than trying to remove only one or two and trying to get the job done at weird angles. Even if you have to do it multiple times.
• In the case of above, cussing is allowed.
• Wiring slack is important, especially if you are going to install the Earthshaker sinking institute mod. In my case, I made sure everything was together and working before ordering the mod. (timing worked, there was one in stock, I think there may be another as of this writing). Anyway. when I had assembled the playfield originally, I didn't realize that I twisted the wire that went through the playfield hole and is buried under the rams and a bunch of plastics. It fit fine for my working purposes. But it was a problem when I went to do the installation of the mod because the twist (actually a wrap around a bundle of wires) made it so I couldn't install the modification. Had to teardown a bunch of parts to get the light uninstalled, untangled, then reinstalled...
• Not all cabinet heads are the same width. The work I did on this machine was done in one room of the house. When I went to move the cabinet (doing in pieces since it's apart anyway) into the game room. Surprise, the head doesn't fit through the door. Now I need to take that off and bring it through separately. What's a few more screws and wires.

I'll add pictures a little later.

It took way longer than I planned, but another Earthshaker arises from the dead. The machine is complete, and I was able to add the sinking mod.

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