Look at my pic, there's a 4-5 inch extension on the right side of the cat I had a muffler shop make to fit my '92-'95 Si exhaust system. I think regardless of what header/cat combination you use, your still going to need a muffler shop to make it all mate up.
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Andy - Reinstated
Hybrid Forum Moderator
'06 Subaru Legacy Spec B - Stock, for now
'98 Civic EX - CTR headlights and grill, Kosei K1's, for sale
'90 240SX - SR20DET that will never get installed, project car.