Offer a discount to prior owners to entice them back to them brand. It's unfortunate though that a bad product still haunts them. I know they have improved but I still remember the trouble that car gave as do other workers at work who would never touch one as they all know somebody who had a bad one. Bad perception can kill sales.
Interior material quality - The big 3 and others should pay attention to this as you spend the entire time in the vehicle. It should at least be of decent quality. As I said, perception can kill sales.
Why would you want to go out of your way to REMIND people that the Pony was bad? It was sold over 30 years ago!?
Sorry to be so harsh but I can't see the Pony killing sales. Its best forgotten and dredging it up can't do anything positive.

+1
Maybe Ford should 'pony up' for the Mustang II and the Pinto for that matter. The Mustang II killed interest in the ponycar era (along with gas prices), and people DIED in the Pinto as I recall.
I personally was scarred as a child to find out that 'rich corinthian leather' was a marketing pitch. Chrysler owes me a Jeep Wrangler.
I've said this before in other threads. I'll put a twoonie (BIG MONEY) on the line for the first automotive scribe that either:
DOES NOT insist on mentioning the Pony, Stellar, or Excel in writing about ANY current Hyundai review.
DOES mention the Pinto in the next review of the Ford Fiesta or Mustang II in reviewing the 2010 Mustang, in the same 'complimentary style' the Pony is used. Or the Citation and the Malibu.
Lets MOOOOOVE on here people. The Pony is dead. Long live the Genesis!