First look on the back of the front door for a manufacture sticker. At least that's where they put them now. If you find one, it will have the date of manufacture on it. That still won't tell you the model year, but if it says "1969", you'll know it's not a '68 model. You can also look for an emissions sticker under the hood, again, if it came with one back then. That will state the emissions systems were approved for a specific model year.
A '69 model could easily have been built and sold in '68. August is about the typical cutoff when they start building next year's models, but Chrysler came out with the '95 Neon in January of '94. That's really pushing it.
Nothing in the VIN. Indicates the date of manufacture but one number does indicate the model year. It's possible they switched to the new model year while still using up a supply of parts from the previous year. Hoods can be switched too so don't base everything on what your hood looks like. Chrysler has a very extensive archives that people use to determine how many of a model were built, with which options, colors, etc. I don't know if AMC did that but if they did, it's likely Chrysler would have that information now. If you can't find that information on the internet, visit a Chrysler parts department and ask. They used to have parts listings for AMC products right after they bought the company and most older dealerships will still have those books. Some of the older guys might know how to get to the archives. For Chrysler, the last half dozen digits in the VIN. Are the serial number unique to every car. The archives can tell you exactly which day and hour that car was built and at which plant.
As a last resort, you might ask the sales manager when the district rep. Is coming to that dealership, then make an appointment to speak briefly with him. They typically visit about once a month to meet with customers who have a complaint the dealer is unable or doesn't have the authority to address. They can warranty anything and pay for repairs on out-of-warranty vehicles if they feel it's the right thing to do. They also have a huge list of contacts within the company. If they don't have the information right there, they will get back to you with it. Getting back to people is a big part of their job.
Thursday, April 12th, 2012 AT 8:00 PM