How to measure input shaft
 

I have an R154 tranny out of a late model 2.5TT soarer from Japan. I have to measure the input shaft length. Am I just measuring this from the tip to the base (only the visible part) or all the way into the casing?

or if anyone knows if the J-spec 2.5TT soarer's R154 is 195mm or 160mm it would be awesome.

thank you