I live in Roswell. Modular Powerhouse is one of the best, if not the best, Mustang shop in the country. They are in Alpharetta, but recently bought Mustang Services in Woodstock. MPH is in the process of consolidating their operations into the Woodstock location. Andy Barth (part owner) does most of the high performance builds. Tim Barth (part owner) does all the tuning using a DynoJet and SCT tuning software. Go check them out. www.modularpowerhouse.com
If anyone reads this, there's two activities going on today, Mustang show at Hooters of Cartersville 12-5 and at the old MPH shop in Alpharetta at 2-3, there is a couple lads getting together, since they have to pick up cars.
I live in acworth and there is an 1/8 th mile track in dallas, just off of hwy 120. they have test and tune on fri and actual racing on sat. If anyone in the area knows of mustang gatherings let me know