My initial reaction is that it is probably not genuine (colour looks to be off, green paint appears to be on top of chips, crimps do not look correct, very sloppy trim painting on fuel tank).
Any chance of a photograph of the underside?
Without seeing it in the hand, it’s difficult to be 100% certain but, given that the colour looks not quite right plus the nature of the axle crimps, I would suggest that this is a repaint. However, I could easily be wrong, so what do other Members think?
I went directly to the axle crimps and thought they do not show a typical Lesney finish and why is the extreme rear axle so short the body seems to be squeezed inwards for it to reach across the body.
Here is the last image with highlights.
DSCF6683 highlight in shadow image..jpg (94.64 KiB) Viewed 1119 times
George is refering to the strenthening brace which was added to the underside of the metal area directly connecting the bottom of the cab to the tanker chassis.
The Green model in George's picture is flat at this area with the Red model having the additonal 'Brace' casting.