right i think the cat has collapsed inside and after just shellin out for cam belt and set of brakes im skint ....so i plan to cut the bottom out of the cat take all the gubbins out and weld a plate back over the hole....will this be ok......also i want a bit more noise and money issues and the fact i dont want a massive pipe hanging from the arse end if i done the same with the back box as the cat would it just sound s**t and would it effect the performance in a bad way?????