What is wrong with '93? Other than the Hypereutectic pistons?
87-88's are Speed Density but can be converted to MAF very easily. This is a must to support any mod's.
89's are freaks and by far the fastest out of the box.
90 and newer have an airbag and in 93 they did away with the forger pistons.
Now, the question is will you find a stock Stang or even want one? Probably not.
I recommend a road trip to Florida. They're cheaper and cleaner down there.