Pigtails
Hey there Kev75, I see you just joined last month... welcome to FTE!
Before I recommend new a pigtail harness for the headlights in your 2006 Superduty, I just want to make sure I understand you correctly...
When you say you got "new headlights" that are "not sealed beams", do you mean you just got some new aero headlamps, which not only replaces your sealed beams, but also replaces the plastic trim bezel that surounds your sealed beams (a la XL style)?
If so, then the Motorcraft Pigtail Harness Kit that you want in order to substitute the aero headlamps is Motorcraft Part Number WPT-793 .
Here is a pic of the WPT-793 pigtail connector end:
The above pic is the connector you want.
But just to make sure, and for your own visual assurance, the pic below is what I'm guessing that you currently have to connect your old sealed beams. This connector is called a WPT-301. Don't order the 301 when you see it in your search for Motorcraft Headlight pigtails, otherwise you'll end up with another one of what you already got.
So, get the kind that looks like the top picture... Motorcaft WPT-793.








