The hq van i purchased for the shell has a number stamped on the cowel, The old bloke i bought it from purchased it from a local council auction in 1976, it was a former dog pound van, and he informed me that the council stamped all its cars as identifiers for assett management, he bought all his cars from council auctions and they all had numbers stamped on them, So i belive some local councils stamped their cars for there own purpose. and the numbers meant nothing to any one but them,

PS this is only my opinion based on what the owner told me, Food for thought though.

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Sorry forgot to mention it is a former victorian council van ,and i do have various old rego papers and the number does not appear on them.