The four wires are as follows: #33 W/PK (AOD Neutral safety), #32 R/LB (AOD Neutral safety), #140 BK/PK (AOD Back-up lights) and #298 P/O (AOD Back-up lights). On my 67 there is a 4 pin connector at the firewall with 2 wires in it for the Neutral safety and 2 wires in it for the Back- up lights (both #140 BK/R) I simply connected one #140 BK/R from the 67 to # 140 BK/P(AOD) and connected the other #140 BK/R fron the 67 to #298 P/O(AOD). It doesn't matter which one to which one. Find the wires running to your transmission back-up lights and hook them to the P/O and the BK/P. It's that easy. If you have any questions email [email protected] and I'll try to help. Rob