I don't see any existing thread for this but there's only a few so perhaps this could be merged into a bigger and more interesting topic. My apologies to Frank (and undoubtedly a few others that I don't know at all), I appear to have missed you (the only possible shots don't go above the knee, all the tandems that I can identify don't correspond).
I have one trike with a tailbox. Could that be Mr Larrington?
The more wonderful will be in QG's topic devoted to that.
Eagle-eyed viewers will see that there are twice as many photos as subjects. Wot happens when amatchers do the work of pros!