Your VIN would indicate it is a late truck, built after 11/80.
Position 12 = 'B' which means the Canada plant rolled out 100,000 units under 'A'
and your truck was unit 124,668.
Although Ford did build a half million trucks in 1981, this occured at several plants.
Even if Canada put out half of all production (doubtful) that would still only total 250,000.
Canada wouldn't have built 125,000, July -Nov 1980 then the other 125,000 Dec 80 - Jun 81.
Too many clues for this truck being built after Nov 1980.