Another Driveshaft question.

They do the calculation for the length of tube
so that there is enough room for front yoke slip into the tranny.

That makes it too easy.
I was told there are two lengths of 727 slip yokes, so I guess you would have to take yours to them so they would make the correct calculation. I noticed that mine is not splined inside completely to the end. I would hate to run out of splines and twist them off on a hard launch.