It is a very common problem to keep breaking transmission mount bushings on the 1982-2002 GM F-Body Camaro and Firebird cars. The cause of this is the torque arm suspension system. The front of the torque arm mounts to the tailshaft of the transmission. The constant stress from the torque arm pulling on the transmission tailshaft causes the transmission mount bushing to fall apart in little time.
Cheap replacement rubber transmission mount bushings just don't cut it. The best cure is the Prothane polyurethane transmission mount that Spohn Performance carries (click here). You may have heard the stories of poly tranny mounts causing driveline vibration, etc. That is very true of another brand, but not of the Prothane mount we use and sell.