mar6.
Joe's Muffler in Adddison is the only place I would ever suggest for that sort of work. Many times a replacement cat that one shop wants to install is way more than you need and Joe's can get after market and remanufactured cats at a fraction of the price that no one else can come close to meeting.
The shop is on Addison Rd and right by that car wash. As was once common around small shops, they are "good ol' boys' there who don't rip anyone off. AND stand behind anything they do.
Speaking of "good ol' boys", if you ever need alternator or starter work, Richardson Generator and Alternator at Greenville and Main (Beltline) has been around for years, they do work like that for about half what most places charge and also stand by their work. If your alternator goes out, they can rebuild it on site and insure it works as good or better than new. I've had them work on my ski boat starter and alternator in the past along with sending friends there for almost 20 years now. Very solid shop.