You're close:  From the outside, take off the plastic cap at the pivot post of
the wiper arm, unscrew the nut,  Now you have to wiggle and maybe pry (put
a piece of wood against the van) the wiper off, it may be a bit difficult.  Then
take the wiper arm off, and put it back on in the "correct" position and test
before you screw the nut back on.  NO NOT pivot the wiper while it is on the
post as you will wear off the teeth.  The nut has to go on quite snugly as it is
mainly friction that holds the arm on,put the plastic cap back on.  IMHO you
do not have to go up under the dash to re-position the wipers.  Malcolm

John wrote:

> My right front windshield wiper does not appear to be not loose but it rests
> just below the window line and then hits the rubber grommet between window and
> front part of the cab when operating.  I have a 90 Wesfalia.  I checked my
> Bentley's but  thought I could move the arm up a little bit just by just
> loosening the external screw rather than go through the glove compartment. But
> that did not work and now that screw does not move at all.  Do I just go through
> the glove compartment and is that how I align the wiper arm above the window?  I
> am--obviously-- pretty new at tinkering with my van.