You should have it. Let me know if you need a different one, I think I have them all up through '74.
There should be a red / green wire going to the two fuses Mark mentioned, the left lights are fused to terminal 2, and the right are fused to terminal 4. There should be two red wires leaving terminal 4, one for the front and one for the rear. If you have left lights the switch is good, so it is either the fuse, fuse block, or wiring. Remove the fuse, check for continuity to see if you have a good fuse. Even if the terminals look clean, get a small wire brush and clean them, reinstall a good fuse, turn on the parking lights, make sure the left lights are on, if so check for power on both sides of the fuse at the blades that hold the fuse as well as the terminals (mine had a break between the blade and the terminal). If that all looks good, pierce the insulation of the red wires leaving terminal 4 and check for power. This is a last resort because it creates a corrosion point in the wire insulation and can become a weak point later, but at this point the lights don't work anyways. Let us know what you find and we'll go from there.