Unplug it (right rear corner seat support) and stick a few fine strands of copper wire in the female ends of the plug then plug it back in. It's just a switch that makes continuity when the belt is plugged in so essentially your compleeting the circut all the time this way. I stripped the strands of wire out of a piece of 14 gauge I had laying around.
I just did it this weekend and I'm a much happier man now. I can hop in and move the truck 300 yards without having to put my damn seatbelt on.
-Scott