I went out this morning and using the loose boom (everything is on the
ground) to act as a long straight edge across the two vertical rails.  The
difference between the  far port corner of the transom and the far stb.
from the imaginary straight  line across the two rails is barely a quarter
of an inch from  a perfect  90 degree angle along the midline of the boat.
That is, I think pretty true.  So I was obsessing on the wrong spot.
However, an improvement I think would be to angle the bottom 1" SS pipe
just a bit so the wheel is at right angles to that portion of the transom
where it rolls up and down. Or, give the wheel a bit of bevel so you get
the same result.  I understand there is a strip or "track" that the wheel
rolls on in later versions of this set up.  I'll retro fit it so the force
is more evenly distributed.  So really, no problem here.  Thanks for all
the advice and suggestions so that I could see the light of Stan's
engineering.

Chris G
Enosis