Mike,
Those little stick outs are little stake pockets. The top one originally had a hole on the bent,angled top side for a hole but now it's closed on mine. The one underneath the rear fender is only a side panel stiffener. It's a stake pocket that I cut on angle to reproduce the original one.

The bottoms lip kick out on my panels are 3/4", but there's room for up to 1".
My panel sides, I tried to cut to 18 3/4" and it came out at 18 7/8" which seems perfect. I'm not sure how these pictures turned out but here is the diagram I drew before I got it bent.

The top side (the bent part) I cut at 4 3/"4 but I ended up trimming off 11/16" in order to have a nice gap to weld on.

http://s1372.photobucket.com/user/foxj12/library/?view=recent&page=1

Last edited by Fox; 06/13/2015 2:07 AM.

1970 Chevrolet C10
Grandpa's -- My first truck -- In progress to shiny
Follow the build in the Project Journal
1950 Chevrolet 1-Ton Dually
"Ole Red Girl"
In the Stovebolt Gallery
More pictures here
1951 GMC 9430 1 ton dually--Shiny! | 1972 Chevrolet C20- Rusty- the puzzle box lid for the C10 | 1962 AMC Rambler American- my wife's
Parts trucks-
1951 GMC 9300 | 1951-GMC 9430 | 1951- Chevrolet 1300