I work with a trust worthy shop in Marietta not the side of town you want but they service some of the guys Impalas from the SS forum it's NAPA Premier Service Center at Address: 1280 Powder Springs Rd SW, Marietta, GA 30064
Phone:(770) 428-2520
Fred is the owner, Mike the service manager, and I think Kevin is the B Body expert. If they can't do the work they will know a shop you can trust.
Jeff