Sharif once mentioned "Elite Auto Body" out on old Greensboro road - Jump on Jones Ferry Rd from the 54 bypass and head out toward University Lake (you should pass a Burger King on the right) You go over a small bridge over University Lake, and then the next traffic light, turn right (can't turn left) onto Old Greensboro Rd - it's a little ways out (I'm guessing 3 miles or so) and it's on the right. It's easy to miss the sign as you pass by. The shop is set back from the road. I chatted with the owner for a while who was in the process of painting a GN.
Sharif has also mentioned "Peach Auto Body" somewhere in Durham, but I can't say more than that.
The GMMOC guys have had various luck with bodyshops & might offer some suggestions too.
HTH
-Greg