When I had my Jeep I had an off-roading mis-hap and was getting sweated by the police in the area, so I used Boulder Muffler and Alignment (IIRC) and they hooked it up and did clean work.
2005 Ford F150 SuperCab FX4
1964 Chevrolet Impala SS
1998 CSVT: 354HP/328TQ @ 10 psi, now gone