I would leave it! Just think, back in 1968 an original ford dealer painted that on there...it's a piece of that cars history. If you're a crazy stock buff like me, it's unique.
I think at car shows it would make a great conversation starter. "What's Coberly Ford?" - - People really get a kick out of seeing more than just an original car, but they also love learning about some things that dealers and owners used to do back in the day.
Brad