Correct, they only built something like 7 boxes.
There’s a video on YouTube somewhere with one in. They did homologate them. But rarely used. Ffd 6 speed was favoured. Though 7 speed manual was used in safari. These was then replaced with the 6speed xtrac m-sport box from 97 onwards

Ken’s car is geared for 136. Most I’ve seen was 127 mph on a single track Belgium lane. I’ll tell you there was no room for error, this was in a straight of 850metres then into a 90 degree left between two houses.