That still won't keep them from breaking the glass, tearing up the steering column and trying to steal it. I had hoped that the club would be a visual deterrent when they looked through the window and discourage them from breaking into it.
I saw someone's build thread on here and they had some chains going around the frame and through the holes in the wheels so the wheels couldn't turn easily, but that seems like a lot of trouble to have to remove some heavy chains every time I want to drive the thing.
Another option would be to have some sort of ring on the floor of the cab with a short chain and padlock going up to the steering wheel, but that would be easy to saw through as well, unless it were hardened steel or something. I've seen something like that on some military vehicles.
As of now, when I park it at home I pull it right up to a dead end barrier beside my house and pull my daily driver truck up right behind it until it touches the 4X4's rear bumper. That way even if someone wanted to steal it, they would have to break into the other one to move it first. So far this has been effective at night while I'm at home. Someone broke into my neighbor's car that was parked beside it, but they didn't bother mine. My worry is what could happen while I'm at work and there is no truck behind the 4X4 to block it in.