As I'm going through mine, I'm documenting via digital photos ,creating files/photos on the computer(saving on an external) and posting on here when questions arise. I am not sure who now is keeping the data base on 68's since Ed B's departure from the site. Another reason being, if anything ever came missing ending up on auction ,I have some sort of proof the parts are mine.
Distributor for example.) Just do a before/after pic.
As far as your question: I'm in favor of painting. Like has been suggested, maybe just feather over the area you want to display as not to fill the text.
My car was covered with goop out of the dealer, so none of those numbers have seen the light of day since 68.
To me it has been sort of fun gathering and filing the data...bit of an OCD thing
I strongly recommend picking up a copy of Jerry M's book. Has been a real time saver and a wonderful reference. Well worth the money.