muley,
I have a 35K unit, PTO driven.. I forget the brand name, will have to check. I think it's a Winco, just not sure. It's big enough to run a home with electric heat, and a farm with live stock. It's a 540 rpm model, and it takes some thing like 65 hp to run it. We use a 150 HP tractor with a 1000 rpm PTO to run it. Use an adaptor on the PTO shaft, and run the tractor at about 1,200 RPM. It's really good on fuel with 120 gal of fuel on the tractor, we can run it several days without adding fuel. My dad bought this gen set 30 years ago, but it sets inside a bulding...So it still looks OK.
Regards, Kirk