you will have to cut out sections of your bumper to fit the OEM fogs in place, and also drill a mounting hole for each.
the switch should simply plug into the harness inside the car... 93s had it in the tweeter, 94-96 in the center console, i'm not sure about 92.
wherever the harness is, just plug in the 92 oem switch and you should be good to go... if you don't have the oem switch then find one that fits and do the wiring yourself.
EDIT:
Instructions for a 94-96 (same minus switch)