In essence the TR7 was more of a successor to the GT6 than the TR6, although there was no carry-over of parts, and was to be called the Bullet or some such. Apparently US dealers insisted on the TR name, hoping to sprinkle a bit of fairy dust on a rather uninspiring car, and thereby devalued the TR brand for ever.
Which was a shame - I have fond memories of my TR6, but never lusted after its successors.
Fjemog