if we do one from gemini bridges staging area out towards green river/white wash, there is 0 miles of pavement unless we ride into green river for gas, and i am told that it's legal to ride an ohv in green river as long as it has ohv registration. i'm not sure if it has to be utah registration or if they are reciprocal with other states for that purpose.
there's nothing that really 'requires' a plate in moab except inside the national parks, or riding right through town (or doing the complete porcupine rim loop). everything else can be accomplished either all off-road, or with only a couple miles of pretty remote pavment.
I might be dragging along a bud of mine. He is a QUAD rider but he is a driver. Mabye we can bully him into buying a bike from you Rick. What time are you thinking of heading out?