The older serie special did not have a sunken datewheel and with a quick datewheel swap it looked a million dollars.
I would concentrate on a gen 6-9-12 dial with a lello or similar datewheel and give the glass some chief ar coating and you will have a pretty nice rep.
I also changed the caseback on my old one but it still needs an A1 caseback to get it correct but these have not been repped.