If you look at the Light Chamois interior color on page 3 of the 1980 section. That matches your truck pretty close. Well some of it.
I would not trust those color chips though. Some of the greens that I know to be green, look blue to my monitor as example. I'd still go to the paint store and look at the actual chips. Some of the paints are metalic, and metalic chips do not scan very well, hence the possible color differences I'm seeing.
Thanks for sharing this though. It will no doubt help others in the future.