FWIW, Bill Piggott has a photo in his omnibus TR originality book of the later type switch on a late TR3A, with the bracket turned like the early TR3A shown above. The switch is mounted with the connections facing downward, and the wires come down behind the bracket, and turn underneath it, so it's practically impossible to get your foot on them.
The photos in my TR4 owner's handbook seem to show the same thing (although it's not entirely clear).
So, while the evidence is kind of thin, it's my belief that Frank has his switch and bracket installed wrong.