Picture on of this post shows the 2 styles of brackets side by side. The lower bracket doesn’t have the reinforcement welded onto it, I think the early ones were like that and tended to bend as shown in the picture.too.
I went out and checked my long bed 4wd and it needs the longer reinforced bracket.
http://67-72chevytrucks.com/vboard/s...d.php?t=163508