Removable doors are the way to go. It is a very easy mod on a lot of RBVs, I did it to my '86, a buddy's B2, and a couple others. You take the fenders off, then one hinge at a time, leaving the door closed. Drill the pin out of the hinge and replace it with a hitch pin, put the hinge back on, and repeat. You leave the doors shut so they stay lined up.
I have no idea if it is legal or not. I keep the doors on most of the time anyway. The only real reason I want them off in the first place is visibility when I'm out wheelin.