backup lights stay on

My 69 Barracuda with 904 trans has backup lights that stay on. I replaced the 3 terminal switch with no change. No amount of adjusting the selector fixes the problem. The lights are not on when it's in park but do come on when in Reverse, drive, 2 or 1. The center terminal (NSS) works properly too. Temporarily I just disconnected the 3 terminal harness at the trans. and bypassed the neutral safety switch. Any ideas?