Everythings the exact same except for the knuckles, depending on when the kit was originally purchased. (talking as a whole on superlift kits)
There's 3 different Superlift knuckles out there and there's 3 different kit part #'s depending on the year. 98-00 PVH hub. 00.5+ Live Axle with 1 set of caliper holes(discontinued). 00.5+ with 2 sets of caliper holes.
On an 03+, you'd want to make sure the knuckles have dual caliper bracket bolt holes. If it doesn't, you'll have to downgrade your brake rotors to the 11.2" rotors found on 98-02 trucks.
'01 XLT disguised as a '03 Fx4 Level II
Big. Loud. Slow. Bright.