For anyone that cares...
I did the swap of the Dana 44 into my, stock height (or slightly sagging) original Dana 35 equipped 89 LDT (two door). The orgiginal drive shaft is definitely too long - it might be OK with a slight lift (~1") but it'll be close - Thant the next phase in my project so I'll keep you posted on that.
I ended up using the drive shaft out of a XJ with a 8.25 rear end (which, like the 44, has a longer snout). The drive shaft works, but I think it probably actually a bit short. Hard to tell really but I'm thinking that the up and down motion of the rear axel is only realistically going to cause the drive shaft to move in and out of the slip yoke by a few millimetres tops (I'll do the actual math at some point when I have time) and there's a good 1~2" available to feed that slip yoke with the shorter drive shaft. Seems to be working OK though - at least on the street. As mentioned, I"m planning on reworking the rear springs so that will provide a bit of lift, might just be enough that I can re-use the original shaft. and with bigger bump stops, I don't think I'll get into trouble with the slip yoke.