I got this for one of my girls. It sat for a long time and I replaced a lot of parts.
Here is my issue. New wiring harness has 2 3 pin connectors for dual headlights. I have a single headlight with 4 pin connector.
I am not finding an adapter or replacement 3 pin headlight.
I have no issues splicing wires, just wonder if anyone has had this problem and how they wired it.

 

First find out why it has a 4 pin connector. Normal lamps have 3, earth, lo beam and hi beam. Cars quite often have 4, the extra being for a parking lamp but this doesn't seem to be a "thing" on ATVs, (though a legal requirement here in the UK, for road legal quads.)