For the ’62 Cutlass I recently finished, I found the pipe from the Y-pipe to the muffler from a company that advertised in Hemmings for vintage exhaust pipes. I believe the company was called Classic Exhaust. An aluminized pipe was about 70 bucks. The pipe came in 2 pieces, one piece was flared at the end and the other press fit into it. It fits well. I don’t know if this pipe is the same for the Jetfire or not, but you might give them a call. I have been meaning to call them to ask about Jetfire exhaust parts, but haven’t had a chance yet.