Guess we need to find a salesman's handbook from a couple of quarters or a few of the
order forms to see if gold was available on GT's
Maybe even (not sure how accurate they really are) an Arm Chair estimator to see what it lists
Did find a copy of an early (June 68 so still preproduction
order for but even though it has an area for "Accent Stripes" there are no colors or codes listed as there are for interior, tops and exterior colors and many other options
Interestingly there are many things listed on the sheets that are lined through and a note from (just guess) the dealer or salesman indicating that option was not available. On this sheet there are 6 different things lined through - include some exterior color choices and three "new" exterior colors added.
Looking at earlier years and 70's also I see no place to indicate a choice of tape stripe color other than the "accent stripe" color listed on the 69 version. Guess they would need to write a request and possibly even use the DSO system to get a particular color.