Hi Swill,
its a tricky question, originality versus safety. Personally, I think theres always a reasonable compromise, with my vehicles I aim for 'as it left the factory' condition, but on most WW2 vehicles the correct lighting in my opinion isnt up to modern road conditions. I really like Jimh's approach, carefully positioned and well thought through subtle modern lights, allowing the original lights to take their correct position.
You mention your Albion, which is of a similar age to my '53 Brockhouse trailer. From new it had trumpet style red rear lights only, no indicators, but within two or three years all similar (Sankey style) trailers had been field workshop modified to typical British army glass lense units with the four fins, red for stop and tail, and orange indicator. I believe around this time Austin Champs went through a similar change.
My '61 Land Rover has the four fin glass units, and I am perfectly happy with them, I suggest you fit those, for additional visibility you could then always fit bayonet fitting LED bulbs.