hardware for rear spoiler

Unfortunately it all depends on the manufacturer of your Saleen spoiler. They each use different hardware from each manufacturer. My old saleen wing had threaded inserts molded into the bottom and I simply used a 3/4" long bolt and washer from the bottom of the hatch. 3 on each side plus one hole for the brake light wire.

Another thing to consider is that they also use different methods of mounting them and you still might need to fill a few holes and drill a few others on a GT hatch.