ok this thing has been sitting in the closet for months now, i installed the plog from these guys and now because i am expecting another child i need to save everything i can. so i want to put in this bad boy myself. i will just have to pay the $70 to have the resonator with a pipe. So what i am asking is anyone have some pointers on how to get this done? i heard a few members have problems with the rusted bolts and whatnot. so i wanna hear it guys

 

Get it as high off the ground as you can. Get it on jack-stands. Shoot down the 4 bolts with PB Blaster and let it soak over night. Also hit the oxygen sensor with it.

The next morning, hit it again. Then go eat breakfast. Hit it one last time, then get your tools ready.

Extensions and swivels will help get the rear exhaust manifold bolts from underneath.

I physically couldn't get the bolts off my car and had to take it to a shop with a lift and a torch lol.

 

I agree with Chibi's advice.
Here's some stuff from my install:
'04 Monte Carlo SS - ZZP Downpipe

Instead of jack stands, I lowered the car on a couple of wooden boxes (originally built for when we did the floor pans on my '84 Camaro). I first tacked the bolts holding the back of the downpipe to the rest of the exhaust. I recently had all that apart to replace the gasket between them. So that went easy (newer nuts and bolts). But, if you are not lucky enough for that to come free, you may have to drill it out (which is what I had to do with the gasket issue).

I got the manifold to downpipe hardware out with a couple of LONG extensions (brought the ratchet down to me making it easier to swing). I believe I had to put a pipe over the handle of the ratchet for leverage (kinda like a breaker bar).

It all went pretty easy. About 1-2 hours of messing around and not being hasty about it. Pre-soaking the hardware is very wise.

 

I think imma tackle this sat. What size mm are those bolts?

 

Not sure about where it connects to the catback but the bolts to the exhaust manifold are 15mm (at least on L67s they are)