T18 Swap Driveshafts

So I should be getting the tcase onto the T18 soon and next I'll need driveshafts. I have a pair of clean and really low mile 1310 shafts from an old project and I want to have them shortened for my Jeep. The shop I use just wants a number to cut to. So if I measure yoke to yoke, I was thinking of calculating my driveshaft length so there is about 1.5" of uptravel available and the rest all for droop. Of would you have the driveshaft cut so youre in the middle of the slip when the vehicle is sitting level? My thought is that my droop will be more than my stuff so I shouldn't need to leave too much compression in the shafts.

 

the local shop I use only need the measurement from center to center . never had a problem with that
and have had a few cut or lengthen

 

Me too.

 

I'm using the local Fleetpride and perhaps that will work this time. Last time I was in there (which was a long time ago), the driveshaft tech wanted to know how much to shorten the shaft I gave him. I was doing a Dana 44 swap into my MJ which is exactly 1" longer so I had it shortened 1"...this worked out no problem. In this case I have the before and after trans/bell/adapter dimensions so if he's uncomfortable suggesting a size then I'll take a punt on my guess. Worst case I need a new shaft made not the end of the world.