Dennis,
You don't need to change your wiring harness to make the headlights work properly .... perform this test first and let us know if the headlight motor lifts the headlights.
With the engine running, increase the engine speed to about 1200 RPM's and then try turning on the headlight switch. Increasing the RPM's increases the battery voltage and causes the relay to work.
If that works then we go to step 2.
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