The rave CD will show where the all the plugs are. From what I understood, If it didn't come from the factory with it, One shot grease, available at your local dealer, will be the last time you have to replace it. I thought I read something about a sticker on the radiator shroud or a yellow paint marker swipe on the drain plugs indicating one shot was applied. I don't think they did it in '84 but you are saying your axles aren't factory so maybe it was done. Maybe someone could validate what Im saying since I'm kind of a noob at this myself.
better yet, do a search for one shot grease and start reading. I was gonna post you a couple of links but there is so much that applies to your question you are probably better off reading it yourself.
hope this helps!