I have just had a Eureka! moment and it feels very
good, even if it took a while for the penny to drop.
I have the side window out of the
vehicle while I am getting rid of the rust and it finally penetrated that
the aperture (inside the body flange) and the outside flange of the window frame
have a fixed relativity to each other, so I measured the body flange and the
radius of the body flange, added the difference, and I have the extrapolated
correct radius of the window flange......
Sorry everyone, it just took me a while to work it
out.
Les