D82U pony magneto, trans slip, brakes

I'm getting ready to move my D82U home from where it has sat for several years. It sat there, because when a neighbor was backing it up the hill, it jumped out of gear and he nearly lost it over the hill (no blade on and no brakes)

When I got it, the coil was missing and the pony was run with a battery and auto coil. I got a proper coil and got it working, and stored it. I checked it today, and it sparks on only one cylinder, testing with a wire stuck in each tower. A little fooling around seems to show it sparks from the tower with the smaller gap. Could it be shorting through the graphite track on the rotor? Can I clean the rotor, or do I need a new one? Available?

As for the brakes, the pedals are solid, so I assume the joints are just rusted/frozen

AS for the jumping-out-of-gear... hopefully not bad gears or sliding collars...maybe misadjusted or broken lock pins? Am I likely to be able to hold it in gear with rope lashing or foot on lever, long enough gto drive it a mile to the shop?

Will post pics as I tinker.

Thanks!

Maybe, maybe not. If it's a problem with the transmission lock out you might be able to hold it in gear. If it's a messed up shift fork maybe not.

Thanks!

It seemed to find and go into gears okay, so I doubt it is the fork...but my total Cat-driving experience is the time it took me to get it up on the trailer years ago.