Ideally you wouldn't do it this way, have 3" dp to the cat with the hookups. I already had the magnaflow and is why i skipped it.

Downpipe/cat - Magnaflow 50828 - https://www.amazon.com/MagnaFlow-5082...

Flange for downpipe to midpipe (ebay seller "customfabshopcom" made it for me from the gasket) - https://www.ebay.com/itm/Stainless-Vo...

Midpipe is 2.5" Vibrant stainless + Vibrant flex

Ebay Thunderbolt Cat - https://www.ebay.com/itm/2-5-Thunderb...

Catback is Jetex - if you can't find it check out snabb.us , quality folks.