Jim Ramsey was at the right place at the right time, and after university, joined an advertising agency and became the head copywriter for all Corvette advertising in 1965 or 66

but when the GM management decided to pull out of racing, Ramsey headed for greener pastures where he'd have a job he could enjoy life, and Y&R made Ramsey an offer, but he negotiated that he not just provide ad copy, but be a performance specialist and enthusiast specialist, allowing him to have input to all creative aspects of the marketing agendas for Plymouth’s performance car lineup.

This isn't unheard of, Jim Wangers did this, and more, for Pontiac.

But 4 agencies were fighting for the Chrysler advertising account. What won the business for Y&R was the tagline “Plymouth Is Out To Win You Over” created by newly-hired Jim Ramsey.  

With the successful marketing and advertising launch of Plymouth’s new intermediate muscle car, Jim was also working on material for the new Sox & Martin Supercar Clinics

Then? Just a little something called the Plymouth Rapid Transit System

https://www.dodgegarage.com/news/article/showcase/2022/01/mopars-mad-men-part-i.html

See terrific Corvette advertising at https://francos65roadster.weebly.com/corvette-ads.html

informative article about the Ashtabula Ohio advert at https://www.hemmings.com/stories/article/shot-on-location