If you have headers you will need to buy 05-06 mid pipes and then a 05-06 catback. You will also have to either cut your existing bumper on the passenger side or pick up an 05-06 bumper.

 

Even with stock headers, he will still need the matching mids for his catback.

 

Is there a template to have the other side of your bumper cut?

 

I think PFYC has rear bumper inserts to make the 04 rear bumper duel exit and comes with a templete, but don't quote me on that.

 

You either need to switch mids or weld the midpipe connections from the '04 system onto the '05. Either way, it's a bit of work.

 

I know there are a few bolt on 04 catbacks that have the duel exit look also.

 

So would the Kooks LTs work on an LS1 with the LS2 exhaust?

 

Yes. The headers are all the same, it is the mids that matter.

 

I have an 04 auto right now that has the Dynatech longtube headers from an 05-06 with a Magnaflow exhaust. Looks and sounds great. The mechanic said the hardest part was dropping the steering rack to install the driver-side header.