Here are some pictures of a rear mounted Chinese engine on a Walmart Mongoose double suspension bike. I used aluminum angle and the only tough part was the muffler extension. The cables needed to be replaced with longer ones. The ride is very smooth as you can imagine and after numerous tweaks to get it right, I am very pleased. I originally tried using rubber vibration isolators - Big mistake, it caused the chain to jamb and a sudden stop! Experience is a great teacher.