I've come into possession of an Enya .60, Model 7032, and wonder if it might be a reasonable powerplant for something OTS like a Wildman or even a Stuntwagon.  I did a search and found that Mike Donovan used one on a Humongous.  It's a ringed engine.  Anyone else have any experience with this engine? 

I haven't used the 60 but I've used the similar 45 model 6001 extensively which is brilliant. There were two versions of the 7032 though (called the 60-II) and was Enya's first engine to use a ringed alloy piston. The first version had chrome plated castings(!) then went to the normal surface finish but with internal changes like skirt ports in the piston and a thicker piston crown. RC versions had the exhaust port drilled on the sides for a rotating baffle and later baffles had a slightly larger (1/8") hole to improve idling. CL versions had undrilled exhaust. The 7032 was made from '65 to '69.

I had a 7032 for awhile. Only bench ran it. It was heavy and would turn a large prop in a solid 4 stroke. The deal breaker was that it was timed to do so at a very low RPM, in the high 6 to low 7,000 rpm range. That could be made to work but was to slow for me.
Tried, and still have a 7033 (later) version. I think I bought it after seeing Jerry's run at Woodland. It seems to be timed higher and runs very much like a ST-60. That's the one I would look for but still may be too heavy for the planes you mention. Other's mileage may vary.  

I have one put aside for use in a Rabe Bearcat in the (probably distant) future.

Thanks for all your input.  Not a lot of experience, but sounds like it might be worth a try.