Just be sure to use one l on the order form! [img]smile.gif[/img] Impala's did not come with a h pipe from the factory though. Any cat back for an Impala will fit the 4.3. Any muffler shop can put it in. The cats are the same, your 4.3 has two of them also.
Not knocking the 4.3, but isnt that like putting a rolex on a clock radio? If you put a factory 5.7 system on it, it would certainly not be the weakest link. Hell, you could put twin turbos on it, and have flow to spare.