You're missing the running board apron support bracket that goes on the front end of each apron. It bolts to the running board with a carriage bolt (should be a square hole in the running board) and then to the apron with two additional bolts. It doesn't attach to the frame. See Section 11, Sheet 17.00 of the Factory Assembly Manual.

Last edited by klhansen; 02/16/2019 1:13 AM. Reason: added FAM reference

Kevin
1951 Chevy 3100 work truck
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1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car)
Busting rust since the mid-60's
If you're smart enough to take it apart, you darn well better be smart enough to put it back together.