Hi Bill,
I looks like the only way to get it right is experiment and try to see what suits the individual forks/type of riding. None of the fork oil "weights" as such seem to be the same between brands for the same labeled weight.
I also sometimes have problems with the volume as some manuals give it as a total volume of oil for each fork leg and other times it is given as a height of oil in the fork leg, not always easy to measure the height of oil inside the tube, and meaning a syringe and tubes to try to get the exact height for both forks.
But the handling difference makes it all worth while, just got to have patience.