Took the driveshaft back today to get it shortened. They asked for the measurements from the opening of the output shaft area/seal of the GV overdrive unit to the front face of the input yoke to the Dana. It measures 40". So, I'm taking that this will be the over all length with the extra needed coming from the distance of the u-joint as it slides into the rear Dana yoke, which will be about an inch. That would leave plenty of meat of the forward yoke in the output shaft hole of the GV unit and enough to slide back and forth as needed under driving conditions.....