Slapped an MY1020 on a cheap mini chopper frame I got. Hopefully this helps someone else. It uses the stock motor mount hole locations.

The MY1020 mount holes can be a little off from motor to motor but should be good enough to fit most. Let me know if you need a slightly different version.

The stock chain still worked for me in my case.

The idea is hex head bolts are captive by the mount plate and you can use nuts/washers on top side to hold down the motor. Slide the bolts in before mounting the plate to the frame.