Need your truck year/model for that information. Alternatively, you can pull the dome light, identify the color code of the wire, and find the same one coming out of the headlight switch.
It's best to put your truck info in your signature so it appears at the bottom of each of your posts. Click on the icon that's at the top of every page when you're logged in (just to the left of the 3 vertical dots) and click "My Profile" on the drop-down.