I adjusted the toe today in preparation for towing it to the alignment shop. I wanted to get it close even though it's only about ten miles.
Disclaimer: does the below work? I have no freaking clue! Made me feel better though. Will know when I pick it up Friday!
Tie a piece of string around the rear frame tube. Then stretch it around the tire at a measured distance from the ground. Make sure you have a little helper constantly bumping into the string to make things interesting.
Then tie the other end to a jackstand placed just behind the front tire. The heavier the better.
We have an advantage that most normal cars don't. That is easy access to a pretty dang good center reference point, that is the center wiring tunnel. Take two measurements, I went just behind the seat and just in front of the pedals and measure the distance from the string to wiring tunnel.
Make sure you sight the tape along the horizontal braces keeping it square, otherwise your measurements will be skewed. Move the jackstand in until the measurements are exactly the same.
Then simply use a 13mm wrench to adjust the toe bar until the front edge of the rear tire just barely kisses the string. When you adjust it you'll move the string a little, so repeat the process until there is no more movement of the string.