Old thread I know. I just got a set of mach 1 springs to go in my 84 hatch for $80. I plan on using the steeda x2 ball joint with my new edge front brake set up.
I still have my Mach 1 springs on my parts pile. I liked when they were installed on my Fox. If i ever reinstall them in something i'll likely trim a tiny bit off the front coil to get down to the 01 bullitt spring height.
There's just a little more spring "twist" to the mach springs on the right due to Ford slightly increasing the ride height in 2003-2004 than the 99-02 cars