Thanks again David. Yes I dry mounted the engine last night, inverted of course. Looks great. I'll just order another smaller tank though extreme flight. All their tanks are for gas so no worries there. The prop I ordered for the VVRC21 is the Xoar 17x6. I also ordered a kill switch and a tachometer that plugs into the ignition box. So I'll see what kind of RPM's I get with the 17x6. With a kid on the way and my wife needing me to help with getting ready for that; I'm hoping I'll get everything together and get this plane in the air sometime this summer. Super excited. Still need to order servos and receiver. I'm looking at the Hitec 645MG servos.