I already had a copy of Ivan Stewart's Super Off Road and picked up a second yesterday. After looking at the two side by side, I was struck by the differences in the cartridge labels.
Attachment 4506 Attachment 4507
Notice the difference in the "4 player game" icon in the lower left hand corner of the front label, along with the additional French language instructions on the reverse "Caution" label. Maybe the one with the red "4 player game" icon is from Quebec based on the bilingual reverse label?

