I have an OS46fx sitting in a Tower Voyager and am thinking about moving it to the Extra 300S. In the description on the Tower Hobbies website, it says that the engine can be mounted rigth side up. I have done a search on this plane and the only posts with pics that I can find show the engine at 90 degrees or inverted. Can anyone out there confirm that the engine can be mounted upright? Before you say that moving from a Tower Voyager to an Extra is too big of a move, this is not my primary plane. In fact I have 6 planes, and am just not having fun flying the Voyager. It sets mostly on the shelf while I take the others out to the field. Will probably sell it at our club swap meet. I am just looking to upgrade the plane that I have the 46fx in.