I want to do the swap for my 88 GXL and I understand that you'll need the bearing hub assembly, new rotors, calipers, from a vert or TII. Still I was wondering since the callipers I have wouldn't fit around the brake rotors from the 5 lug maybe is there different rotors I can get that would work just to save in cost, parts are severely limited in my area.

 

For the rear yes, the s5's I believe came in a solid read disc with a 5 lug bolt pattern. I ran that for a while when I didn't have a set of vented rear rotors and matching calipers.

fronts though, maybe there's a model that had single piston up front but not that I'm aware of that used a different rotor than the 4 piston aluminum calipers