Bigbird, you have a great work going on that stearman, really is a super proyect.
The roto engines are made in Czech republic, and yes, they run on gas. Don´t know where you can find them on EEUU, RCShowcase was the dealer, but they went out of bussines. There is a RCU member selling a couple of them for about $500 USD I think.
The 35 is a little to heavy to balance the stearman without tail weight. So I can tray to put the batts on the tail, or maybe install 2 elevator servos. It won´t be pretty, but it will work.
Well any suggestion will be aprecciated.