the original plans show a fuselage made from gutter pipe. I use the plastic folded in a rectangle and have made a removable section of gutter pipe that holds all the servos, fuel, bat, etc. and which the engine mounts to. This can easily slide in and out of multiple fuselages and allows me to quickly go from one plane to another.

I can't tell you how easy this stuff is to work with. I can build 10 planes in the time it takes just to build a balsa wing. I am currently trying to figure out how to build a delta wing. Their are lots of plans on the spad site. good luck