Hi blair.
As has been discussed above, your car sounds like it is an S model LJ & these didn't come from the factory with a handbrake warning light switch. One similar to a SL or GTR one could've been fitted by the selling dealer, but from your description it doesn't sound like one has. It should have a pressure differential switch mounted on the junction block near the brake master cylinder. This operates the BRAKE warning light on the dash.
Is there a problem with your car that we can help you with ? Is the light stuck on all the time perhaps ?
Dr Terry