That's a great find . The Bonanza guy's go Banana's over these Choppers .What ever you do to make your engine fit don't cut any thing on the frame . Or the same guy's will really go BANANA'S ! The Tec OHV is that a Powersport engine ? I think those might be a lil taller than the honda clone engines you can get from Harbor frieght .
That Chopper came with a Tec flathead engine which would be a great way to restore it . But the OHV engines put out a lot more power for the $$.
Look over at minidoodle.com to see what it looked like originally . Enjoy