I saw that generator for sale on FB marketplace for a while, it was only about 1.5 hours from me. While the price and hours were low, they sure did a number on that electrical system. I doubt you will be able to convert without issue to single phase due to the modified voltage regulator and overcurrent sensors. It also looks like they heavily modified or removed the safety systems on there. They even disconnected/removed the wiring from the overspeed switch sensor. It doesn't look like your overload wires are connected either. Looks like a huge safety hazard waiting to happen.
FYI this is coming from a guy who has owned/serviced/converted dozens of 004/005 generators.
(Also have (2) 005 generators for sale currently
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