I am ready to cut out the main engine access hatch for the Byron F-15 conversion I am working on and I wanted to know the best way to make a frame. What I am looking for is a way to make the hatch easy to open and close with BVM type hatch latches. I have not cut the opening yet. Once cut, it is not as simple as putting the cut hatch back due to distortion of the body and hatch. I was thinking about L shaped plastic or carbon fiber and making a square frame for the opening and hatch but the straight frame will not conform to the contours of the body or hatch. Any ideas or suggestions are welcome. The finished openeing will be approximately 12x18 and the dorsal speed brake will sit on top of this hatch. Thanks, Ken H