The story about Jim Clark's death being the reason for the "black badge" is a good one, but untrue. In the late 60s, Lotus was running red and white cars and the marketing director thought the yellow and green logo clashed, so he designed the black and silver one. Colin Chapman rejected them and they were put on the shelf. When stocks of the yellow and green badges ran out, production grabbed the black ones. There was a month in 1969 that the black badges were used exclusively and the story about them being used for the anniversary of Jim Clark's death came to be.
My S2, built in January 1970, is badged exactly like yours, including the wood shift knob. I have the S2 logo on the rh (passeger) wing, but the "World Champion" badge is on the driver's side. Perhaps the interior black badges had been accepted by Chapman. My seat belts are pretty much shot, so the Lotus clasp will probably be scrapped, but I've added 2 more of the black and silver type to the headrests. With all these badges, no one should ever wonder what kind of car they're in:)