They wrote back and said the pins were the same... so I ordered one of the connectors. Pulled the pins out of my connector - they're sliiiightly larger than the ones included with their connector but I think a wee mashing with the pliers fixed that. Just ordered a terminal block from mouser to wire this to (
504-TB345-05 and
504-X31905), gonna find some decent wire for the job, then I'll connect the head to the terminal block, and then swap around the wiring as needed to get 120 volt across both windings. Utterpower sure talks about that a lot but never actually says "here's how". Then the output from that terminal block will be out the same path as it was from the power module; I suspect I will need to disconnect some sense wires from other terminal blocks further down the line.
I noticed my outside power terminals, the big ones... two of them are missing their nuts, cages, and the little wedge that actually clamps the wire. These aren't in any way a standard part I'll be able to find... are they...
If I get it all running and generating power again... and you haven't sold them... I'll definitely buy your battery tenders.