This was my approach to measuring the valve stems.
http://forums.pelicanparts.com/showthread.php?t=328636&highlight=measurement+instruments&page=2
Ultimately I put a pin gage in a V-block, set the millimess, pulled the gage and put the valve stem in. Decades of wear made the valve stem appear straight to the naked eye but hugely tapered under the instruments. Into the garbage the old valves went, replaced by NOS ATE.
Bill, welcome back to the Forum! There is a really good thread on here about a guy who built his own flow bench. . .
http://forums.pelicanparts.com/showthread.php?t=455530&highlight=flow+bench Enjoy