O.K.
I want to clear any comfusing about three different pipes.

The large inside pipe goes over the bypass was made early last year. That pipe work very well for all class engine. It require to clear some of the wood former to fit the pipe.
The latest pipe made exact to the original stock pipe. But there is two different size. One is for 32-36 lbs thrust class. The other is for 36-45 lbs thrust class.
When order the exact duplicate to stock pipe. Please let me know how much thrust the engine you are using. So I can made to the correct size.

If you guys had one of the large pipe. That pipe work for any engine.