The screws I bought were too long. They bottomed out in the bottom of the tapped holes. I ground about 3/16" off the ends so they did not bottom out. The lock washers had diameters that were too big. Metal was removed in appropriate places.
Not bad, 90 minutes to run four screws. And folks wonder why retired folks are always busy.
Cutting and bending to fit
The motor is a tight fit. I had to re-drill some holes to slide the engine another half inch forward. Then I had to recontour the forward trim on the motor mount bracket because it was hitting the frame. Even at full forward the air cleaner was banging into the seat post. And that was AFTER I carefully customized the air cleaner cover by dropping the motor on it. The cover required additional whittling to make it fit. An air cleaner with no cover is of little use.
The key was too long. I had to cut it to about 1/2" so the clutch/pulley lined up properly.
Back in the old days this would have been called a "Goat Festival", or something similar.