55.2-59 Cab corners question

[toymanbob]

I'm finally ready to tackle cab corner replacement on my '55.
https://67-72chevytrucks.com/vboard/...d.php?t=820010

The rust only extends up two or three inches from the bottom of the corner. The new sheet metal corner has at least 12" of metal above the corner and I am wondering if I should cut it down or use it all. What is the consensus?
Bob

[dsraven]

is this a 55 first or second edition truck?
some pics would help us see your predicament
generally strip the outside and inside of the area to ensure it is a solid as you think and somebody didn't already beat you to the patch panel area years ago. this also makes nice clean metal for better welds. poke at it with a sharp tool here and there, lie an awl, just to make sure there isn't something lurking that will haunt you later. then mark the area at the top of the max height you have to work with for the patch panel. compare the max height with the height of the area where you have good solid steel to work with. hopefully the patch panel is a lot taller, lol. next decide if you want to cut the patch panel down or use it as a full height. body lines and curves can be a deciding factor here. try to weld close to a body line to limit warpage but also leave room so you can planish the weld when done, as in, leave room for a dolly on the back side so it doesn't end up too close to a body line. cutting a patch panel down is a pretty common thing so you don't have to use it at full size if you don't need to. an area with a shorter weld would be great if cutting down the patch would help with that. next cut out the bad steel, cut the patch panel slightly bigger than needed. place it over the hole and fit it up for best fit. alot of aftermarket patch panels need to be tweaked to fit the vehicle, so get that over with. then place the patch over the hole and cleco or clamp it in place, and cut the body along the outer edge of the patch panel using a thin zip disc if possible. this will fit the hole to the patch. using a scribe along the edge is also a method if zip disc is not an option. remember that a cutting disc takes some space away from the fitment, basically the thickness of the disc, so if tight fitting panels are needed for, say, tig welding, then the scribe method may be better

[mr48chev]

Generally it is cut up above any rust or issues and trim the replacement panel to fit.

I'm going to add that it is probably prudent to make the cut an inch or so Minimum above the floor so you can get to it with hammer and dolly. Plus you need to do the cut in the easiest for you to work on spot.