One last check is to jack up the rear and put some GOOD jackstands under the axle tubes. Start, put in high gear and put your finger on the shaft with the square hole the end of the cable fits into. If it's not turning there then pull the plug out and check both the gear there and the one inside the trans. Sometimes one lucks out and only the driven gear is bad but since I don't have a horse shoe in my butt it's usually the inside one or both.
