One of my favorite ride experiences was on a gas powered Twister in 1975 and 1976 on Johnny's United Shows, though I think it was booked on and not owned by JUS. It looked like it was out of the 50s, and while watching it one night, it shook to the point a fluorescent tube came loose and crashed on the wooden decking...no one hurt. The reverberation of the gas engine could be heard from far away and was certainly a drawing feature of it. Watching it being assembled, one of the workers told me that it was the fastest ride on the midway and would reach 65mph. It traveled in a plain box trailer, that I remember seeing straw in. The center was towed separately. The tubs/carts were orange with white curved stripes and black trim.
Hearing that about the Twister, do you remember when Deggeller Magic Midway had a Tip Top with a center load, but also had a straight job carrying the tubs and other parts?
I have seen a few Loop O Planes in recent years with gas engines, one booked in with AofA and then at a still date in Ga with a show. Boy they sure did sound good when they started them up.
In the late 70s McBride Brothers came to this area with a ground mtn Eli with gas engine I believe, I know it was ground mtn though.