On my '38 coupe the only real adjustment is up and down done using the screw in the bottom of the housing that moves the reflector. The truck has a different housing however and I don't know if the adjustment is the same. Keep at it, where there's a will there's a way.

Save a life, adopt a senior shelter pet.
The three main causes of blindness: Cataracts, Politics, Religion.
Name your dog Naked so you can walk Naked in the park.