My skirts have a couple of screw/bolt holes at either end and have bodykit fixing tape (like double sided tape type stuff) running along the top. From googling pics there should also be a few bolt/screw holes along the underside as well.
The front splitter has about 5 plastic brackets with bolt/screw holes inside the splitter which attach to the bumper and a couple on the edges that bolt under the arches. Again with the bodykit tape along the top.
Not sure if I've explained this well but heres Motty's original thread asking pretty much the same thing! http://www.tezzaworld.com/viewtopic.php?f=11&t=8209
1999 RS200Z Blue. Kakimoto Exhaust, Exedy Stage 1 Clutch, TODA Racing Flywheel, Tein Coilovers, Advans RG Alloys, TRD shortshift, Räzo knob, Nardi Classic Steering Wheel, Recaro seat, Walboro GSS342, Power Enterprise air filter.
Coming soon: Rotrex C30-64 Supercharger, Caldina GT-T Injectors, Power FC