RE: Stunt Chimp
AG Bill,
The plans show a radial engine mount that will take any of the Cox .049 engines with tank. I think the Aeromaniacs recommend using a Black Widow but a Babe Bee should work fine. With that engine, the 30' lines should be about right. I would recommend a 5 1/2 x 3 prop and fuel with 15%-25% nitro and about 20% lube (castor/synthetic mix).
If I remember correctly, you can download both plans and assembly instructions. I would suggest at least reviewing the instructions to look for any hints or improvements.
Good luck and enjoy.
George