I've done it myself, it's quite a bit of work.
Even the disco transfer will be a bit short on 4.7 diffs. If you're not running 3.54 diffs (which don't give particularly nice low ratio), consider a 1.003:1 conversion kit. The ratio calculator on the Ashcroft site is a godsend. Other than that, any LT230 will mate to any five speed regardless of ratio. Beware of the spline wear issue, though. Early transfers didn't lubricate the splines on the input gear adequately, wearing the input gear and the output shaft of the main box. If not already fitted, get the upgraded cross drilled input gear, but the main box is quite possibly in a poor state already. Output flange wear on the oil seal lands, intermediate shaft wearing the casing causing a leak and diff gear wear are also common faults of the LT230 worth looking out for. The LT77, I know less about.
There's the ongoing "throw it in with full time 4wd" vs part time 4wd conversion debate too. Personally, I hated the feedback through the steering running with UJ's rather than CV's, but there are other members here who are happy with it and swear blind it's fine. The conversion can either be a kit, or a spot of heavy welding in the diff with a bearing fitted to support the front output shaft.
Its possible to mount the gearbox up without butchering the chassis by fabricating some mounting plates, though you'll have to scallop the bellhousing crossmember to clear the front prop. Handbrake can be adapted to suit the series linkage and the clutch is easy enough. You'll need a custom transmission tunnel and possibly mod the floor/seat box. You may already know all this, of course!
Given the work, I'd buy a spare series box to rebuild in the kitchen with quality parts and keep a rebuilt spare handy!