Yea, there's lots that I've wished I held on to. Unfortunately, growing up with a father who sells this equipment, there was always another tractor just waiting, so we never really held on to anything. He'd say,"It's just a tractor. I've got a whole shop full of them." On the positive side, I've had LOTS of Cubs and Cub Cadets to play with over the years, so I can't complain.
I've got a 105 here in my shop now that I just moved in today. It's going to get a complete overhaul. Someone already put a brand new Kohler 14-hp engine in it, but they butchered the frame doing it. So I've got another frame that I'm going to modify the correct way and then build up the new tractor. It's going to be a Cub Cadet 145, something that never existed from the factory.
Good luck with the mounting plate. It should not be too difficult to figure out.
Bill