I just got a injen ses true dual catback locally for 120$. It's kinda rough but hey it was cheap. It was off a 350 and is the old angled tipped design. I need to know first whether its gonna fit at all and second what size extension I need. I'm pretty sure I need two 8" extensions but i just wanna clarify before i order. Also what portion of the exhaust do the extensions go in at? Any help would be greatly appreciated. Thank you!

 

I believe that's what you need if it's a dual exhaust. Isr makes extension pipes, try a Google Search and you'll find what you need