That second link might be what I needed, thanks John.
I see Carolina Blue listed with the old Dupont number 926-98371
That's the same code found on the buildsheet of the 70 Chevelle that rlw68 linked to. Just so happens I have a big picture of that car I can blow up and it visually appears exactly like the blue on my 72. So I'm pretty confident that is the shade I need, and I should be able to cross over that old Dupont number.