Opinion on universal wiring harness
Yes but for a '67, so cavities and colors will be different on your car.
In general, the concept is as shown.
Illustrated is the headlight switch on, powering the low beam relay (black wire).
Some people prefer to plug into one of the original headlight connectors. Thats how crackedback makes his harness.
I think Daniel Stern has a scematic for that on his website, although its not too difficult to figure out from above.