layz

i have the mufflers welded up to the back seat belt bolts and the mufflers where they are welded up to is a factory plate with the bolt sticking through are hanging down a little..i tried tightening up the bolt but it is tight already..i got under the car and there is a gap from the plate to the underneath of the car...i am wondering where the mufflers should be welded up under the car..they are single chamber flows...