Well imho, I would be careful and not do anything that couldn’t be backed out. I would also save the parts if it really worries you. I can tell you as time goes by, originality has become less important unless you are talking about the really rare cars out there. Just watch Mecum or BJ and you will see the restomoded cars pulling ahead of the “numbers matching” crowd. I fall into the group that likes to add factory options to my car. So far I have added PDBs, Rally’s, hood tach, clock and fold down seat. I also switched to a 4 speed from an automatic. Maybe I devalued my Sprint a little but someone could always go back. All I know is it is a hell of a more fun car to drive, especially wrt the 4speed and disc brakes.