It's not a full VIN, it's a partial. 1 or 2 numbers, one letter, six numbers.
On the upper surface of the cowl, below the right hand wiper, nearer to engine bay than glass. It's about 3/8" high, stamped into the steel. Generally "upside down" when viewing from the front of the car.
You know the VIN on a '67 is on the left hand door jamb, correct? With the conversion, it may have been moved, but it would seem that it should be there somewhere.
Vikki 1969 Goldenrod Yellow / black 400 convertible numbers matching