I'm not a huge fan of Jeep trails down there. There is plenty of single track to ride in the area. Just stage from the Super 8 parking lot in Green River Utah. The single track starts on the south east corner of the parking lot. You'll ride under I-70 and the railroad tracks and end up on the Dubinky trail system. Good times out there for sure. You can ride pretty much to Moab if you had enough gas. Also check out Rabbit Valley in Colorado. If you are feeling like some gnarly riding check out 5 miles of hell (not for newbs). It's one of my favorite trails down there. Another good one is the slick rock trail. Hells revenge crisscrosses the slick rock trail if the slick rock trail is to difficult for your guys. It'll be fun no matter what you ride really.
Maps and info:
http://www.bookcliffrattlersmc.com/#!riding-areas/c4xp