Very, very earliest A7 tail light

[Brandis]

My A7 is a bit of a tie capsule. Untouched for 70(?) yeas.  It still has the rubber gasket outline and different hole pattern for a very different tail light

[Brandis]

 I found something similar. A swing arm Shooting Star. But the fender shape and the hinge on my bike are different.
I remember seeing a photo of the A7 at the '46 Paris Motorcycle Exposition and I recall that the Speedo was in the tank and the tail light was sort of Buck Rogers.

[Greybeard]

Might it be like this?

[Greybeard]

I'm sure I've seen a much smaller rear lamp on the early bikes. I believe there was no brake light filament in the bulb.

[Greybeard]

This page from Drags may be helpful.

https://draganfly.co.uk/product-category/bsa/sparesparts-for-bsa-a710-b3133-c101112-m202133/electrical-abcm/lighting-abcm/tail-lamps/

[Rex]

I have the 480 on the rear of my '51.
Looks a bit incongruous if I honest, and I'll likely replace it for a later larger type over the Winter.