Stock Rear Slip Yoke, How far does it engage?

I just went to replace the u-joints on my 99 XJ and when I got under the thing the first thing I noticed is that the rubber boot was torn that covers the slip yoke and quite a bit of spline was visible, over an inch without question. It was almost like I couldnt pull the two ends of the boot together. The suspension is totally stock other then replacement rear springs so that it doesnt sag, but factory height, how far is the slip yoke supposed to be on the splined output shaft at factory ride height? It almost looked like it wasnt on far enough as I couldnt pull the boot together...

I dont know, anyone have any insight on this? Now I have to source a new boot to.......