Rhys,
I don't know about that MGA taillight arrangement, I was just trying to show a RHD version and it was late.
May have to give up on this # 7 question and move on but the research is fun.
I took a photo of our old unrestored MGA in our shop and also a Fairthorpe photo I found from a similar angle.
MGA
Fairthorpe Electron Minor
Ken H