i just did my 66 with stock headlights Heres a link for 63-66
http://67-72chevytrucks.com/vboard/s...d.php?t=397695 , but looks to be the same for all trucks i used this one because it shows you what wire went to what post of the relay:
http://67-72chevytrucks.com/vboard/s...elay+headlight and my low beams look like high beams now, and also i think all my interior dash lights are brighter also, it is very simple install!