GForce Engineering

I bought a 3.5" one piece aluminum driveshaft for my 2012 Camaro SS from this company. The included instructions state to mount the rubber boot side to the differential. My installer did as these instructions state. While the car was on the lift he tested for clearance, no issues, however when the car was lowered and driven, the balancing weight banged against the rear heat shield, damaging it. I called G Force and Billy answered the phone and said to just remove the shield, it was done and again on the lift test no issues. But no when driving the car, the counterweight banged into the E-Brake, so it had to be removed. I called GForce again spoke with Austin and he tried to blame it on the installer, I read the directions sent, and he said these were the WRONG directions, they were for a FORD MUSTANG, not a Camaro. He said someone would call me back before the end of the day. 15 minutes before they closed (4 hours after I spoke with Austin) no one had called, so I called them. The person who answered the phone again blamed it on the installer, and said the shaft could go on either way. He then tried to start talking to me about a Mustang driveshaft. What does a Mustang driveshaft have to do with my Camaro? Why did Austin tell me the wrong installation instructions were sent? If the proper one's had been sent, NONE of these issues would have occurs because the counterweight has plenty of clearance on the transmission side. He hung up on me. $811 for the driveshaft...$200 for labor, which would have been only $80 if the correct instructions had been sent. Damaged heat shield that will cost me $63. Another $90-$120 for labor to put it in the proper way. They blame it on the installer following the directions they provide and hang up on me? What kind of people operate a business like this?