A good part of that time involved perfecting my front and rear motor mounts. Here are the pics:
The front mount is an improved version of an older design: engine studs to transition plate; transition plate to angle pieces via 5/16" Grade 8 bolts; angle pieces bolted to doe tube via 1 1/2" muffler bracket. The angle pieces are locked together by 4 short 1/2" bolts.
Study of the older design reveals a weakness: a horizontal crack had developed through the metal where the transition plate bolted to the angle. Although more than half the metal was affected, the motor was still quite solid but failure would have occurred at some point. I'll have to keep an eye on this area although that mount lasted well over a year.
The rear mount is a simplified, cleaner version. The key was using a 2" x 2 1/2" rectangle of 1/4" steel as a transition plate. I cut that out if s larger piece of steel using a hacksaw (not having any kind of metal band saw at my disposal) and it affixes to the seat tube via a 5/16" U-bolt.
My first runs either new engines have been smooth and zippy. New fuel line. New chain. New CDI. This thing is brilliant, a real blast to ride.