Chris, great find on the engines. I would stay with the engine mounting and attitude as it is on the plans. It just looks right and the engine is a lot easier to tune! I will think about another after the projects on the board are completed. I am working on a TF F4U .60 size right now as well as a TF P-51D for our club pres. Putting an arf together for a friend who is having surgery and getting a float plane ready for next year. I kind of am the fixit guy for the club also. The repairs keep me in fuel, as my fee is usually a can of 15 or 20% for the repair. It is just part of the hobby that I enjoy. Not too many kit or plan builders in my club. It is a shame that tissue and dope means tp and drugs to some of the younger members! I can remember when silkspan was included in the kits. Glad you are doing this P-63 over. I really enjoyed how it flew. As I said earlier just too much slop in the ailerons due to their mass. As a side note, I built the Spit that Sterling kitted from plans and it flew great. I built the Platt Spit years ago and I would say the Sterling flew better. Once upon a time there was an article about scaling out the Spit which I obtained from the author. Another project in my mind. Good luck with your P-63. I will follow this thread for a flight report.