Thanks for the info to all that have chipped in. I have doing some more research and probably besides glow, the 2 best options for this plane will be in the 40cc range with the Brisson and ZDZ being the front runners. I was told BME does not manufacture anymore lower than 50cc and the smallest DA is 50cc. Zenoah is darn heavy same as 3W as per some info I was able to find.

I saw your pic of the moki installation and that is exactly what I am trying to avoid, cutting the side of the cowl. Did you tried to mount it inverted?

Well, I dont want to be a bother but if some have good info on weight of the Brisson and ZDZ or any other recommendation for powerplant for this plane. I refuse to cut the side of the cowl.... and trying to keep plane below 14.5 pounds. I will probably look into CF elements and other lightening options (no structural) in order to compensate for the excess weight of the gas engine.