Good question. I wonder if there were silver ones early on? My two buddies with '66's had black belts, but both were later builds with original V8's and not many dressy type options. Just the basics.
The first one I ever saw was, I thought, a '66 owned by a family friend. His was Yellow, with I'm pretty sure a white interior and black, or maybe medium gray belts.
And no back seat if my memory of getting bounced around is correct.%)
Paul