1980 honda xl 125

Hey guys. I recently got an old 1980 Honda XL125S for free. And I'm looking to fix it up and make it into a decent trail bike. I was curious though, I really don't like the look of the 1980 seat / gas can. Could it be possible to take the seat and gas tank from the 1984 model (the year the bike started to look like a modern dirtbike :P) and put it onto my 1980?
Thanks for any help, and I'm sorry for the wall of text.