I have a 93 4WS and the harneses for the fogs are behind the bumper, where they should be. Im not sure if the switch wiring is there or not, havnt ripped out the console to see.
I think in the 92 the fog switch goes in the left tweeter grill, you might check behind there to see if there is an extra plug.
Your also going to need the fuse, there should be an empty spot in one of the fuse panels, probabally the underhood panel.
Thene again, maybe fogs weren't an option in a 92 USDM lude.