I've done more exhaust systems on late model f-bodied cars than I would like to admit to and can tell you that if done by a reputable exhaust shop will come out well and last a long time. Be careful what muffler you decide to go with because some of them can make your car sound like a fart can. I used to have a complete muffler/tailpipe assembly from a '97 Z28 that would've bolted right up....would have been nice to send you a pic of it out of the car. At any rate, it's a simple job that any halfway decent exhaust shop can do...Stay away from "Ravin" mufflers, they sound like crap on the 6-cyl cars and stay away from the "Mac" system for your car...the internal welds are weak and they have a tendency to break up from the inside out.
New Toy- Stone stock '88 T-bird Sport in need of some TLC
1988 Cougar XR-7- HO/T-5 conversion, cracked block prevented from reaching full potential.
RIP '88 T-Bird....email@example.com...best sleeper in So. Jersey, now it's taking a permanent dirt nap.