I'm not familiar with a 37 cab but generally speaking you are advise to take all precautions to avoid distorting your cab when you replace sheetmetal. Some is more critical than others structurally, but all play some role.

Be sure the cab is on a flat surface and reasonably braced. After you cut the damage and tack the replacement in place, hang the doors to see if there is any problems with them. If not, finish welding by skipping around your patch. Do not try to run one continuous bead.

Be very careful, go slow and you should be fine.

Woody
Your Brother in Bolthood

My 1951 half-ton 'Ol Red

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