Hi Larry,

> Could you review for some of us, what these numbers are supposed to mean?

IIRC, the number in question represents the number of revolutions per driven mile at a predetermined tire size. Put a bigger tire, speedo reads lower. Smaller tire, faster. Once upon a time, you could purchase speedo drives  gears from VW to compensate for different tire sizes. Keeping in mind that VW speedometers tend to read optimistic. 

> Don't all vanagon speedometer cables connect to the cap on the front
> wheel and therefore turn at that rate?

Only the 2wd Vanagons take their drive from the dust cap at the left front wheel. Syncro speedos are driven off the front diff. If you put a 2wd speedo in a Syncro, it will twice as fast.

BenT