I would do as suggested above. When you have the lift, SYE ect. in place, then measure front the center of the rear yoke to the center of the front yoke. Then add 1 inch. That should be your expanded length. Tom Woods or Adams. I just picked up and Adams drive shaft for $200. Should fit me 2" lift. Also, what type of axle you are using can change the length. I have/had a Ford 8.8 in both of my XJs. I did have issues with the one as the 8-1/4 was changed to the Ford 8.8. The Ford had less than 1/2 inch extension. It would bind sometimes and get squirrelly. I'm sure Tom Woods or Adams will help when you give them the length between the yokes. Also, might contact them as to the pinion angle needed for the rear axle and you lift.
I did do a Hack-n-Tap on both of mine. With a 6.5 lift and I assume heavy OffRoad, then I'd go with a true SYE.