Watch out for careful drivers!!! I'm away on an ego trip. Will be back on Feb 30. I'm not an Auto Mechanic, but I play one on TV. I charge $0.02 for every opinion and I take Paypal. Plan B is always better than plan A, by definition. "We have no time for comment, every man will make his own. LET IT BE MADE WITH POWDER AND BALL!!!" I recommend invoking MIL-T-FP41c when machining and fabricating I used to think beer was bad for me, so I gave up thinking. Sometimes no nonsense makes sense, in a sense. You can't teach a new dog old tricks. Honk if you're Amish
I'm not sure how this compares to your '57, but on my '47 I bought a bunch of different Greys and found the Krylon Fusion Matte Deep Gray 2914 to be a good match to the original color. Here is a picture with the original on the passenger side and the Krylon on the driver side. I sprayed all the greys on a piece of metal and held it next to the interior panel and took a picture. I found that the lighting that I was using caused the new paint to look different than the original when pictured. I then did a test spray on the rear door jamb and in natural light determined this to be the match.