The general jist is the 707 was yellow and gold. 706 was yellow and black. But no announcements to be found about the new 706 color and 707 continued to be produced.
I wordsmithed the verbage a bit:
(3) Alternate yellow/black custom interior offered late in the model
year. Most 706 lower interior parts were black instead of the gold
in a 707 interior: carpet, lower doors, kick panels, dash, etc.