Which to do first cab corner or rocker

[Squareforceone]

I need to weld in cab corners and rockers on my 84 and not sure where to start i assume do a cab corner first then the rocker?

[chengny]

I am not a body man, but this procedure (for replacing both the rockers and corners) makes sense to me. Credit to Chucks Chevy Pages:

Putting them on is a process. You need something to work off of that is aligned properly. If the bottom edge of your door is rotted away, you can't work off it. If the area behind the front wheel is rotted completely away, you can work off it either. If your Cab Corner is rotted away, you can't work off it. The more of these that are in tact, as far as the edges go, the better guide you have to align new parts. Furthermore, there are factory clearances between panels. Doors and Fenders can be adjusted a bit, but the Rocker Panels, and Cab Corners must be perfectly aligned before they get welded on.
This is why when I restored my 77 K/20, I had a parts replacement order I followed. I'm not sure if it's the GM way, but it made sense to me. I was replacing a lot of parts, in fact, all that I described above. Since I knew my doors were aligned properly, but rusty, I left them on, and started with the rocker panels. I left enough strong steel on the edges when cutting off the old Rocker, to make welding on the new ones easier, and possible actually. I also removed the rotted out Cab Floor Supports. Some rust can be so extensive, that the floors would have to be replaced before the Rockers can be welded on. Sometimes, the Cab Corners have to be replaced prior to replacing the Rocker Panels as well. As long as the Floor Pans are solid enough, as well as the Cab Corners, the Rockers can be welded on. Since I was replacing the Rocker, and Cab Corners, I didn't weld my new rocker to the rotted out Cab Corners. I did weld the new Rockers on the three other edges. After I had the Rocker aligned, I tack welded it all around the three sides. I then cut back my front Fender behind the front wheel, and peeled back the sheet metal, to gain access to the front edge of the Rocker. I welded the front edge. I then removed and replaced the front Fender. I then cut off the old rotted out Cab Corner. I welded it to the new Rocker, and the edge of the door frame. I did not weld in between the bed and the cab, as I planned to remove the bed later, and weld the Cab Corners, while replacing the Bed.

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