Nice plane. I have the GP STM version and it also has a DLE20 with pitts muffler. Nothing sticks out and in fact I had to extend the pipes out of the cowl with some tubing. It has an 80" WS and flys easily at 1/2 throttle. Ihave a 14lb Pt-17 with the same engine and it has no problem getting around. This plane should be way over powered
You should put in a smoke system since weight won't be an issue with this engine, trust me. Look into using Solartex for the covering, I just recovered my wing with it after an accident and it almost covers itself and it has the real fabric finish. Available from Balsa USA. I'll post some pics later.