Help, 72 duster NSS/Back up light harness hook up.

Last night when i got home i pulled my NSS harness to get a better look. I found that the 3 prong plug used to be the whole thing. Someone has already cut the brown with yellow tracer wire and ran that to the starter relay. The other 2 wires are purple and white? any ideas where i can splice these to for my lights to work. only temporary until i swap motors and replace all wiring. i will load up a couple pictures as soon as i can.