If the 92 is in good shape keep it as a good looking daily driver, even if it's 2WD. Get a 4WD XJ, when you can, but have fun in the short term.
Add the recovery points, and console yourself to wheeling only 90% of the fire roads and trails (at speed if desired). I would add a rear locker and hitch (to tow the eventual 4WD XJ project) and purchase basic recovery straps and tools.
Where can you go in 2WD (lots of places, just take a buddy vehicle to help with the unstuck chores)?
Most of the forest fire roads are green circle easy rated 2WD roads. Keep to these roads and you will not have a problem (stay away from the most difficult black diamond roads).
In the desert, a good chunk of the Johnson Valley and Stoddard Valley OHV areas offer great speed roads and washes to run. Visit the Slash-X Cafe off of Highway 247 and run either direction until you find a dirt road heading west, and run till you find Hwy 15. Look for flags in the bushes and you can have fun on the off-road race course.
The same fun can be found in the Dove Springs OHV area north of Red Rock Canyon State Park, and the greater Jawbone OHV area. Burro Schmidts tunnel is 2WD fun, with a little history. There are many areas near the aqueduct in the Dove Springs area that make fun little MX style truck tracks. Stop by the Red Rock Canyon Visitor Center, off of Hwy 14, north of Mojave and pick up the Friends of Jawbone Map for legal roads and trails.
If you stay out of Doran and Odessa Canyons, around Calico, you will find most of the other mining roads in the area are 2WD capable. This leaves considerable terrain to explore.
2WD and 31's will also get you onto the beach outside San Felipe, but test your skills on the sandhill behind the El Cortez Hotel & Club La Pesca campground, before risking a deep beach stuck (the tide will bury your XJ if given a chance). The Baja race courses also offer great fun in 2WD, just realize some areas need extra throttle to plow through the siltbeds and washes.
Don't let these guy's discourage you, they all drive 4-door stationwagons

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