Shortening Drive shaft

[JackieFan]

Does anyone know off the top of their Swede how much the short side drive shaft needs to be reduced by in order to fit it to a S12/S13 vLSD hybrid diff using BOTH S13 output shafts? Is it just the difference in length between the S12 output shaft and the S13 output shafts+CV joint? Also has anyone got a picture of an S12 driveshaft without the CV joints on the ends?

hope that makes sense