69 was 503 light green - your 69 blazer would be 503 light green
71/72 was 518 Medium Green
They are close - but not identical when you see them next to each other.
Edit - I updated with a screenshot of the two greens when somebody got a spray can of touch up paint and got the wrong shade from
this post.
It's
easier to see on paint that hasn't been in the sun for many years. 71/72 518 Medium green paint on firewall - smaller square is a spray can of 503 light green. They are close.