Just look at the old Mopar musclecars. The ones that seem to garner the most value today were the oddballs that dealers couldn't sell back in the day. For example, when new many dealers could not give away cars like Plymouth Superbirds and now they are highly collectible. I would suggest to look for the lowrunners and special editions and those will be the ones that will be the most valuable later. Also, if you are looking to retain the value on the car, keep it COMPLETELY stock. The OEM restored and unrestored original musclecars have the most value. Just my two cents worth from being in the Mopar musclecar hobby for the last 15 or so years.