Welcome to the Forum. I had a 93 GC Laredo with the V8, Auto, Quadra-drive Infinity Sound, Towing package. It was a great Jeep. I have a 2000 now and love it.
The spare tire goes in the rear behind the back seat (driver's side) and leans against the side. If there is not one there you are missing it. There should be some mounting hardware and cover as well.
It sounds like you have the quadra-drive system in yours if it only has Full-time 4WD, Neutral, and 4Low. The Select Trac has 2HI, 4HI, and 4LO (If I remember right
As far as tune ups I would change the plugs, wires and distributor cap. Especially if you thing they have never been changed before.
Not sure about your tranny question or Head lamp haze.
The '93 was a good year. Mine only had minor problems in the 7 years I owned it. Brakes, brake caliper, one broken wire for the electric windows and locks, and the air conditioner compressor was starting to leak when I traded it in. Hope you enjoy it. It sounds like youv'e got the sound system taken care of, now it's time to get it ready to go off road.