Its not too bad, I typically buy complete tierod w/ ends as if you are doing both its really not much more money, then I measure carefully the one I am removing, set the new one to that length as acurately as possible.
Spray all old rusty hardware with penetrating fluid a few days in advance, blast the nuts off with an impact wrench and good socket.
Leave them on a few threads Then to get them out normally a good wack on the side, or otherwise an impact wrench with one of those rod splitters can work.