I have never seen a vin on an engine other than maybe on brand new 1990 plus stuff with the paper bar code decal.
And besides there was no vin on these trucks till the 1981.
Wikepedia is off the mark as far as 1950's trucks as it was not a
vin and more of a serial number with a series designation. There was nothing to id the engine cu in or paint color or anything else like that. Series designated capacity, frame length etc as shown in the operator manual specs or truck spec sheets. And the numbers/letters represented originating factory and manufacture date.