Since it's a Ford (I'm not knocking it, had an F150, now an F350), but to change the headlight bulbs, you have to remove the headlight assembly. Then the bulb is replaced then the assembly put back in the vehcile. I don't have my owners manualy book with me at the moment, but I do remember seeing instructions for both the E and F series in it.
Hi sonnyswords. I recently had the same problem replacing a Bulb on my Newmar based on the F53. It is very awkward to twist the Holder from the Housing and I finished up with terrible scratches all over my arms from the Fibre Glass surrouind. I wish you luck. If you find out the trick? Let us all know.
If you are still looking for info?
I finally had time to do mine, man what a PITA, especially for the drivers side.
Don't forget there is a retainer ring, which is the hardest part.
Took me about 4 hours to do both.
Had to remove Batt and holderFro one have to remove and loosen bolts on fuse box tom get the other.
Good LUCK !!!!!