Hi;
My info may be a bit dated but I can tell you what I know.  Handihams
offered a box that connected to some rotator control boxes that gave you a
variable pitch depending upon the antenna direction.  A friend had one and
it worked well.  You may want to investigate if it is still available and if
it will work with your rotator.
Norms rotator service also sold a modified rotator and control box that
worked wonderfully.  I wish I hadn't sold mine.  If you can buy the control
box separately and what modifications need to be done to the rotator are
questions worth investigating.
I'm curious as to what type of antenna you are putting up? A tower can be a
big project, best of luck.  Is it self supporting?
Rich