i have a 92 mj 4.0 automatic with an aisin transmission. my speedometer use to bounce every now and then; then it decided to quit looking through forums i tried the instrument cluster by checking to see if it was a lose ground but no luck there. so i looked again and then tried clocking it with a drill and found it to be dead but the wire is hot going to it. so i got a speed sensor for the tcase but the new part is a plastic three prong system when mine is a metal cased two wire system. also note that mine is longer with a metal shaft to hold the gear further out of the tcase so it can be mounted where as the new one cannot be mounted. what is one to do about this?