My motor is completely stock and I went against a lot of opinions that I would lose tons of low end torque if I went with 1 5/8" long tubes. I'd have to say they were pretty far off because I don't think I lost much, if any, and gained all kinds of top end which would have more than made up for any low-end loss that occured. I would highly recommend a set for your steed as well. They are sweet.
I would also suggest that you consider a complete exhaust system from front to back. If you have to buy one part at a time then so be it. Just install it all at once. This also makes the removal of the old exhaust easier because you can just use a sawzall to cut all the old stuff out and not have to unbolt anything except the headers. Your decision, but my exhaust was a piece of cake to remove and install since I didn't have to try to break all those #%$@ bolts loose.
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90 Mustang LX 5.0
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