I've got a 1976, so has the square rear lights still but no reverse light within. I did recently make up something to add a reverse light, since the loom and the shift housing as the switch etc. Only reason was so people can have some idea of when I was reversing - even if the reverse light might not be at the correct level or angle. I also added a fog light on the same bracket, as the loom as the wiring and the switch is there, although I wont be driving in fog, ie knowingly setting out when its foggy!
I used a bracket from Halfords that I think is used to extent lights when towing something. Essentially its got two round ends on it, like one end of a dog bone, that just happen to be the exact size of a glass type indicator. You can get them clear, and red. The other end I just cut and folded so it sits the opposite side to the exhaust - I know the reverse light should ideally be on the near side, and fog on the offside, but again this is just something thats better than nothing at all!
For the MoT, well mine is exempt, but I do have it done every few years, I remove the bracket with the lights incase they get funny about it, and re-install after. The main thing for me is the reverse light which is very bright and unless a car is incredibly close behind me, can be seen to give a clue I am going backwards!
Oh and I think the place that does all the fancy alloy bits does a more formal / better fitting item, DSN Classics I think they are called.
Hope it helps! Will get a pic if needed 
Edited by maccers, 12 November 2025 - 01:37 PM.