Hi Darren,
Probably need a Fire Extinguisher Expert, but my understanding is that the early tanks, A13, Cruisers etc and carriers all had the early type of extinguisher, the brass type as seen here:
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These would have been in all vehicles up to and probably including the introduction of the 1st Shermans. So lorries and armoured cars, early tanks etc would most probably have been equipted with these. Time period pre war and up to 42/43. Once issued they would I assume have remained in the vehicles throughout the war. I saw exampled of the BrassType in Landrovers and Bedford Trucks in the 70/80s!!!
The late pattern set was I imagine these were made with British Armour in mind ie, the Cromwell, later versions of the Churchill, Sherman, Comet. Although here is one on a Humber SC..
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For this type they seem to start appearing from 43 onwards. I imagine they were designed after the first experiences of the Sherman (Tommy Cooker) as they are much bigger and one would assume slightly more powerful than the previous issue to tanks.
Regarding colour, I have seen them the same colour as the vehicle, a slightly deeper gloss green and red/orange. I believe, but have no specific evidence that the red/orange colour is an early post war development but I may be wrong. As I said folks need to consult their references. Museum vehicles are great and I use reference pics from them a lot but they are not always 100% accurate, bits of the vehicles are often missing and alternatives get used.
If their is a Fireman in the member ship, perhaps they could give more specific data.
Hope that helps a bit, that's my understanding at present, but I'm always open to new data.
Al