Chris at Vintage Brass Plates now has the originals of the i.d. plates off both skimmers and 137, he has identified that the numbers of the sand skimming tractors are 310 and 311 not 1311 as I thought. This means that either Ransomes started a new numbering sequence for the sand skimming tractors or the bloke that stamped them was half asleep and forgot the first 1!!! Whilst I suspect it may be the latter scenario I will stick with what I have and use 310 and 311 even if only as a discussion point.
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