Last year, I replaced my stock headlight with a rectangular Lucas 8 driving light. I bought a Harley connector and pins and did the wiring... incorrectly. I initially wired it to the high beam, which annoyed me.
I tried to pull the wiring out of the Deutsch connector and mangled the wires. I managed to cram them back into the correct spots so the headlight was wired to the low beam but the connection was crap. It would occasionally go out and require a little jiggling of the wire for my headlight to come back on (not exactly safe).
A big part of the original issue was that I didn't have the proper Deutsch crimping tool so my poorly-crimped wires didn't fit inside the connector properly in the first place.
I bought a (relatively) cheap crimping tool on eBay and it works great! I bought a new connector and pins from a Harley dealer online.
Here's the old connector. Note that it just uses two wires since my light doesn't have a high beam.
I pulled the wires out, cut and stripped them back just a little and used my new tool to perfectly crimp the pins on them. Sorry the pic is a little out of focus.
The pins went inside the new connector easily and now my headlight finally has a solid connection.