Hi Bill,
Yes, I have read the " New UAV Helicopter with gas power", and have PM both Chris and Ferruccio. The Synenry 766 that Chris used is not available, the Vario Benzin that Ferruccio used is expensive. The currently available gasser on the market are mostly for 3D flying, difficult to install electronics, Whiplash G2 gasser might be better, but I have not found anyone who owned it and installed the ardupilot on it.