Nice 1st gen! '87 was a change over year. If you have rear disc brakes then you have a 12 bolt rear and 10 bolt front axle. If you have drum rear brakes you have a 10 bolt rear 8 bolt front. These are the number of bolts in the ring gear not the housing. The 2.3 is a carb'ed engine. Not quite as powerful as the EFI 2.6 but gets better fuel economy. With that motor I'd keep tire upgrades to 31x10.50x15. It's also a good idea to replace the factory auto hubs with manuals and repack the front hubs.
That factory service manual is worth it's weight in gold.
KISS Principle = Keep It Simple Stupid.
Your best defense against Murphy's law!