Depends on amount of time you have. From Wellton, its a quick drive down through the Goldwater Range (no loitering) to Tenajas Altas where you may want to climb to the top to the tanks before continuing over to Tule Wells. We have a cache at Tenajas Altas if your a geocacher.
From Fortuna you can drive through the old Fortuna Mine site and south past Spook Canyon and on down to Cipriano Pass over to Tenajas Altas. There is a 4x4 track at the south end of Vopoki Ridge (south of Spook Cn) that you can take NE back up to the rim of the canyon (N 32° 29.009 W 114° 16.783) for some great views of the canyon and Hooterville the marine urban warfare training site to the west. A simulated village constructed from shipping containers. If its still there. An interesting side trip.
There is also another entrance (a gate in highway fence) near MP42 on I8 that goes straight south through Christmas Pass to Tule Wells. Lot of sand wash before rocky Christmas Pass. Fun drive.
BTW, there are sensors all over the place that you will trip, so you can probably expect a visit from the Border Patrol at some point.
Also, here is a website that I got info from before my first time down that way.
http://www.4x4now.com/pp001.htm
BX