OK: I went back and re-measured all five of mine...This time I made sure I was
*not* measuring across a date, or a number on the lug, or across a dent or ding...and I got several different measurements...so the letters/numbers and any dings or dents will affect the accuracy of the measurements...
I also made sure I was as close as perpendicular to the horizontal plane as possible...I noticed that if I went just a bit off 90º that the measurement would change...
The receivers are "fatter" on the sides than on the top/bottom...So the
least measurement will be 90º from horizontal...or straight up & down...That's the one we want...