here is the concept of that we saw in Detroit.
http://i19.photobucket.com/albums/b180/smskinner/auto%20show/0119001034.jpg
http://i19.photobucket.com/albums/b180/smskinner/auto%20show/0119001034c.jpg
personally I would tell him to eat a dick. He had it for 30 plus days and then comes and tries to cry foul. I would also show a him a pic of it installed on your car to show that there is no issue.
your sore due to the muscle fibers tearing. There is no way around that. Lots of water. figure one gram of protien for every pound you weigh and try eating 5 or 6 times a day.
Also sleep get at least 8 hours of sleep.