Ha. Have fun.
The diagnosis is probably right on.
Wherever you have the work done, make sure they know how they're going to get the generator out and back in and at what cost and give you a firm estimate before they start!
I had this same problem, but luckily it was the day before the warranty on the generator expired.
Unfortunately, if your Sahara is like the Endeavor(and I think in '02 they were identical), the 3 hours labor is a joke.
Cummins West in San Leandro did the repair on this, and it took them 6 hours to get the generator out of the rig. Problem is the bar across the bottom of the front cap - the generator needs to slide straight out, but the bar is in the way. HR wanted them to break the fiberglass that holds the bar in place so the bar would drop (taking the generator door with it) so a forklift could get in to the generator to take it out - but cummins couldn't do the fiberglass work to put it back together. Next idea was to cut that bar on each side, then when done weld it back together with a splice plate on either side for strength. Problem is, Cummins doesn't have the equipment to weld aluminum. Had to unbolt the generator door, push a forlift up to that bar, put a winch around the back of the generator and pull forward until it hit the bar, then put another winch from the bottom of the generator to the top of the forklift and lift until it clears the bar, pull forward, lift, etc until the front is resting on the forklift, then move the lifing strap to the back of the generator to take the weight when it cleared the rail in the RV. Repair took 20 minutes, including disassembly, testing, and reassembly time, replacement took another 2 hours.
Cummins/Onan only allowed 3 hours for the entire job. Cummins West (a great place) ate the rest as customer goodwill. Yes, they earned any future service work when I'm in their area as well as good words like this....
2002 HR Endeavor