Big 10/ heavy half

[dtkarst]

I got to looking at my 76 closer and didn’t pay much mind to the paid when it said f44 heavy suspension and such until I saw a square body drove by with a big 10 decal on the bed. I forgot all about those and can’t seem to have much that’s Concrete as to when the first year was. So my questions are, what year did they start the heavy half or big ten deal? Wht makes it one? And did they all come with decals on the bed sides on the upper rear? My bed was replaced somewhere along the road so not sure on the original. From the little I’ve looked up, it says f44 and has the 6200 gawr on the door jamb sticker. Just trying to learn more about it. Thanks