Hi Abufletcher!
The Fokker EIII on page one was build and flown by my Dad. He owned a Proctor Nieuport 28 as well, that was flown with the first rotary engine build by Wolfgang Seidel, the ST540, a five cylinder with 40ccm. That was enough power for that little airplane and we were not sure about the big ST770 in the Fokker. Well, it does look much better than a too small engine, especially with that "open" Fokker cowling. In the end, it proved that the ST770 was just the right fit to the airframe. Sure it is overpowered, but not much. It swings a bigger/scaler prop and having some "spare-power" on finals is sometimes the live-insurance for a WWI aircraft.
The ST770 is definitely not in the G62 range of power. With those 7 cylinders and 14 valves, there is quite some energy waisted to turn the engine.
Go buy that engine, you gonna love it. And it makes a 1:4 Pup a one-of with it's great sound.
Best regards,
David