Not that most will notice. The two main variations are the V6 got a softer spring rate due to less curb weight and most of the V6 cars didn't get the rear sway bar (though many dealers added them on the lot).
1998 Roush: M112'd Aluminum block 4.6L 2V 6 speed track car
1999 SVT: Mostly stockish
1970 Mach 1: Resto-modded monster
2000 Roush #5004 - World's FIRST M112'd V6 Mustang. Sold, but not forgotten.