I just fixed the same issue on my 69 Barracuda. I had replaced the switch and no dice. The connector that plus onto the switch at the tranny end was bad. (contacts get hot and corroded over time and wear out). I bought a new pigtail for the tranny end and that solved it. http://www.ebay.com/itm/141071990823?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649