Fred,
Chris Kvale made his own top tube cable guides in the '70s , too. He used
stainless automotive tubing (brake lines?) and cut the ends on an angle so
that the bottom where brazed onto the top tube was about 1/4" longer that
the top portion...this gave a very pleasing look. However, they were too
small a diameter for modern cable housings. He is now putting larger ones
on bikes that come in for re-paints.
Tom Sanders
Lansing, Mi USA