My toe measuring device had a pair of pointers that could be adjusted to approximately spindle height, after scribing a line at the center of the tread. I always kept a chunk of white sidewalk chalk handy to mark the center of the tire tread all the way around before scribing the line. We would set the distance at the rear of the tire first, and then very carefully move the fixture to the front to check for the difference in toe. It was very important to roll the vehicle forward a couple of feet and chock the front and rear of the tires before making a toe measurement. Even rolling back a little could unload whatever tension there was on the tie rods.
At the race track, we kept a pair of flat aluminum plates about 10" tall and a couple of feet long to prop up against the tire sidewalls, with slots for a tape measure front and rear. After a little wheel-rubbing out on the track, it was not uncommon to have to make a quick toe adjustment between races.
Jerry
