On my 2006 F-250 I have noticed recently that when I turn on the headlights, my dash illumination is very weak.. I rotate the dimmer control and for about 1/2 of the adjustment there is no illumination and then is comes on but faint.. The local FoMoCo service wants 2 hrs labor to troubleshoot it.. Could this be something as simple as the Headlight/Dimmer switch assembly that I could procure and replace myself or???

 

It sounds like it is the dimmer switch. Go to a junk yard and pick up a headlamp switch control module. It contains both.