IMO, not a reason to trade the car in. The problem was more than likely caused by who ever you had put the converter in. Make them pay for the damage if you paid them for the install.
I have no info as I was not there during install. This car has been a nightmare, I guess I should have just sent it to a shop for all the work and not do shit with friends or hookups. The shop was doing it as a favor since a friend of mine that helped with the motor works there. He paid to replace the rear main and oil pan since he did the work for me.