The landmass of Daggerfall would probably be too big for Morrowind. And there are plenty of game engine differences.
There was at least one project to rewrite Daggerfall (http://www.gamesas.com/topic/1058120-daggerxl-the-continuation-ii/). Seems to me like that is a good way to go.
Edit: There is a http://planetelderscrolls.gamespy.com/View.php?view=Mods.Detail&id=4091 mod if you haven't seen that already.