2003 GM not marauder rear end questions

[superliger]

Anyone know a good shop in NJ to bring my 2003 Gm ultimate edition to, to have my rear end gearing changed? i live in sayreville NJ and just moved here so i dont know where any speed shops are.. im looking to upgrade from my highway gears to 3.55 or 3.73 posi diff.. any help is appreciated.. also what should i expect to pay for a true dual exhaust on my car from the manifolds to the bumper?

Erik
Superliger@aol.com

[BK_GrandMarquis]

Look up Outrageous Mustangs in Jackson, NJ. Small shop but he does good work. He installed my differential and gears a couple of years back.

I forgot his name but he is the guy in the BF Goodrich ads that has the fastest time on street radials. I think his last name is Gutridge.