This would be the frame to use if you're going with the big Predator from Harbor Freight. Maybe straighten out the seat tube and weld the motor plate on the bottom tube. Our peanut fuel tanks have a straight flat underside which might be somewhat difficult to mount on a curved top tube like this. Never the less this frame sure stirs the imagination.
View attachment 205436
I guess your gonna delete the chain, sprocket, pedals & chain guard (Chaining)