MSD coil bad? Or does it ground through Mount?

O.k., many of you have read my numerous post about my 3g upgrade and my surging problem. Well I installed my MSD coil at the same time. Today I switched to the factory and my warm idle surge damn near went away. (slight surge as before, doesnt read on tach) My question is this: Does the coil mounting bracket serve as a ground for the coil (I painted mine do to rust) or is my MSD bad? When I reinstalled my factory coil I laid it acrossed the master cylinder and the coil bracket (it should see some ground here).

Did find out that the GT has a catted H pipe. He!! maybe its factory...dont know.

O.k. I replaced the msd withthe stock coil after noticing that the stocker has a thin metal layer around the mount (bright contact area). I did this bu disconnecting the msd and laying the stock coil across the master cylinder and the mounting bracket. I made sure it would ground. The car ran like it did prior to the install. I removed the coil bracket and cleaned the bolting surfaces (sandpaper to all screw holes). I made sure that all these areas where free of paint. When I remounted the msd she fired and ran like a champ. Even let it run for about 15 minutes. No noticeable surging.

I think your right on the H pipe. It gets removed anyway.