Found! 6-19-68 340 engine block.
Here is a can of the paint by Plastikote, #210. Sorry they are upside down, not sure why? I didn't save them that way. This was discontinued 10-15 years ago, maybe longer. It was called Chrysler green that mirrored the blue/green of the 69 340. This color was the only one that got close to the actual 69 340 color. This can is from my older fiend that owned a 69 dart in 69. His friend in 69 had a B body with the Turquois big block. The 2 colors sorry to say were not even close, there was a difference. The lid of the can does not resemble the actual color, the lid looks blue but when you spray this color it is blue/green. There is no info on the internet about the 340 blue/green! Nothing! You won't find anything except for the odd person that has seen the difference, usually a mopar guy in his 70's. The 340 color myth is twice as bad as the Hemi orange myth!! Trust me I have seen an original 69 340 beside an original BB and they are 2 different colors 100%. Anyway I couldn't resist. LOL. At least we can have these discussions, if we had a Ford or Chevy we would be sound asleep by now.
