Am I forgetting anything?

[Jusme661]

for a couple of months now ive been debating on what i wanna do to my 01 GSR..went thru a couple of options and really wasnt fully thinking of them..1st i wanted to do all mugen..header and exhaust, but decided too pricey..then i was gonna go with the Greddy exhaust but didnt know what kinda header i wanted to do..the my bro in law suggested i do an all ITR setup ...looked in to and not too pricey and yet still has that OEM look...
so ive decided i wanna do an ITR Header and Muffler setup, but im trying to figure out if im forgetting anything

1. ITR Header
2. Header Gasket
3. Header Collector Gasket
4. Header Bracket
5. ITR OEM B-pipe
6. ITR OEM Muffler

so am i missing anything? am i able to use my OEM catalytic? do i need a collector flange if the header already comes with one thats 2.5"?

[TegSox]

You talking about a full US ITR or JDM ITR system?

[Samurai_Blue]

i think hes talking about a 2.5" the jdm itr is 2.25" and you will need a custom cat or test pipe. you already have a header bracket, and a header gasket, you dont need those

[SprchdGS-R]

the dc sports exhaust isnt loud and looks like the itr