Thanks for that Rich and thanks for the wave the other week! I spoke with Gerald and he suggested getting a separate main cat which will allow me some clearance flexibility. So it looks like a custom exhaust from stem to stern!
The entire exhaust system is laying in the driveway. I was getting a code for faulty pre-cat on one bank and I need to smog it to get my stickers.
I planned on replacing all the O2 sensors anyway and dropped the exhaust pipe to have a look at the pre-cats (there are two of them). Good thing I did...the forward pre-cat is completely blown out and needs replacing. The other one "looks" fine. This just happened to Jerry B and the blown out pre-cat plugged up his regular cat and left him stranded on the side of the road.
So, the pre-cat/cat header is being replaced and while I'm at it, the 100K mileage banged up stock muffler is also getting replaced/updated.
The pipe diameter before the main cat is 2.5". After the main cat and including the muffler, it drops down to 2.25". Its all getting replaced with 2.5" all the way back.
I figured I would get it all as far out of the way as possible. I'd really like to have the oval tubing and muffler from Spin Tech! We'll see.