I have a '93 gc laredo 4.0 and I'm looking at putting on a cat-back 2.5 exhaust system. Now the question is how much would the piping from the cat-back cost? And from where? Another question, i have an aftermarket muffler already (it was free)and the inlets are 3", if I put it on my 2.5 piping would the 3" tubing in the muffler cause a loss of performace? Could I place it closer to the end to reduce performace loss? or should I buy a muffler to fit? Also how much are mufflers and are they straight through(unlike the VERY restrictive stock one)? I'm on a budget so I'm trying to go as cheap as possible, trying to stick close to $100 maybe a little more for the whole setup. sorry for so many q's and thanx in advance for the info.