The 75, 76 750F uses a large header too, I slipped a 2 1/2" stainless truck exhaust tip 18" long over it. It was 3 1/2" OD from there back so it will hold a glass pack insert for a corvette or cobra side pipe. You would need to slot the end to tighten, use the graphite gasket or other shim material and a T bolt clamp to attach it. I got the pipe from auto barn, the insert was made by patriot, bought from jegs. I welded hangers to the stainless, just an idea to start with. They sounded awesome.