It took me literally years to get the correct mix formula for my Mulsanne Blue - my Brother-in-law is a rep for PPG and in the end he had to got through the tech guys in the states. In saying that, it is 2K paint so will look very different to the original finish in terms of depth and reflectance (I did flip flop between factory acrylic finish or the 2K). So even if the formula was correct, as said in the post above the pigments are different and also it will change depending on the application and flake settlement (wet film thickness of the spray) and what sort of light it is under. Non-metallics have a much better chance at matching, but fading is an issue and as said above, who knows what actual colour it could have been resprayed.
There is a pretty good site paintref.com that lists cars, OEM codes and shows some pictures of the cars with the similar paint option in the OEM colour, this site will also filter into 'Blue Corvettes' which will list and picture every blue Corvette with OEM codes so you can seee what colours had the same codes but different names.
I have attached as an example the Mulsanne Blue list that shows how the same GM code was called different colours. Also pictures of the 1972 GM colour charts as mentioned above - don't use these to match paint! Surprisingly my Mulsanne Blue is very similar to current? Mazda Astron Blue...go figure...but the Duplicolor touch-up pen and touch-up spray was acceptably close to do some out of the way touch-ups.