I thought I had pics of all that guapo...but I guess not. I have some transfer case adapters/intermediate housings/tailhousings (whatever you wanna call 'em) here now and can take some pics of the internal area in question if ya need 'em.
If you do end up having to pull the adapter housing, you will need to remove the transfer case input gear (bull gear) off the output shaft, that will require a bit of muscle and a long cheater bar!
Then plan to replace both the seals behind the bull gear while it's off, no sense in putting it back together and then discovering ya got tranny fluid going into the transfer case.
Have patience when attempting to adjust the shift cable, if the cable is original it's most likely in pretty bad shape and will be a bitch to adjust, a new cable makes the trans actuation just like new! Same for that little saddle clamp that retains the conduit to the mounting stay, that needs to hold the conduit very snugly, any slop in that mount is greatly accentuated when attempting to adjust the cable.