All that stuff came from ONAN.
5945-01-378-7172 is the solenoid, (comes without plug) Part number: 88-20090
There was an NSN for the entire linkage assembly, including mounting bracket, (part number 186-6179). But the NSN was never in the books and was more or less a "secret". The CECOM had the number. I had it from them. There was also a NSN for just the linkage. I will look. But at the end of the day, ONAN provided all those parts. I do have NSN's for each individual part, but I don't think it will help.
Do you have the mounting bracket?