Please note I have cleaned up this thread by separating posts into two disctinct threads:
British WW2 180 Gallon 20-cwt Bowsers restoration and
Canadian 180-gal 20-cwt water trailer info.
There are are differences between the British and Canadian built watrer trailers. Although the Canadian trailers were built to the British design, they did differ in respects of methods of construction and parts like brakes etc. The latter were off Ford CMPs on Canadian built ones. The difference between the Canadian 15-cwt and 20-cwt is one or two extra cross members in the chassis and 20" (instead of 16") wheels on special adapters to fit the hubs.