Here's a good thread on the Custom Two Tones.
http://67-72chevytrucks.com/vboard/s...d.php?t=704629 They lasted from 70-72 and the pic below shows the combos available in 1970, not all persisted thru 72. I like the Custom Two Tone options a lot and they aren't very common (not exactly rare though either). The two tone options were Conventional (white top only), Special (69-70) with white on the top and the very bottom, and Deluxe (71-72) with white on the top and middle. Custom Two Tones were only offered in certain combos as shown in the linked thread and the ad below. I don't have an ad for 71-72 specifically though. Mine's a 557 that someone painted the top on turn it into a solid dark olive truck - a horrible transgression I will be correcting someday! Ha.