Sanity check: Decoding VIN for '69 Dart GTS
It's clearly a slant 6 car.
If it's priced as a clone 340 GTS, buy it.
If it isn't, negotiate it down to that level and buy it. You clearly like the car.....just don't overpay for it.
Clones are the best...all the joy of the original, without the price premium.