btw: Your son's F-100 and flying were Awesome today at the Masters Qualifier!
Andreas used canister header pipes for exhaust extensions on his. I did not examine his install closely enough to ascertain how he pieced it together, but he did tell me the headers were larger in diameter than the Moki stubs, so the exhaust just dumps into the header pipes.
Number one, I did not happens to have an extra set of headers I could sacrifice; number two, I am not sure how to make headers work in this application, as they are not flexible?
My use of flexible copper pipe seemed plausible and relatively inexpensive, but as I say, yet unproven in the air.
You will like the P-47
I am hoping to have the Builders Manual finished by the end of May[8D]