Just saw I did not paste in this thread
Stopping beep beep
You might need this to get the ign cylinder out, so the upper steering wheel cover can be removed ( without bending the snot out of it ). Just so you have it handy in case. Look for a post by JMC, he wrote up the procedure on how to remove it.
Another quick question, when you checked the high beam headlamp fuse #3 in the cab fuse panel, did you have the headlamps turned on, and the MFS pushed forward ?
A quick test ( if you have a steady hand ) is to apply +12 V DC to the pin in the back of fuse #3 ( passenger compartment fuse panel ) with a meter probe or awl.
To do this, have the truck off, and the headlamp switch turned to the OFF position. Either side should illuminate the high beams if the fuse is good.