What's the best way to repair these holes

Hi everyone,

I have a 72 Dodge Demon with same cancer around the windows. So what's the best way to repair these cut and weld or por 15 and expoxy putty or even fibreglass repair.



I'm an ok welder but nothing special.

I will be keeping the car, planning a stroker 383.

Most all the body work is done. We painted the under side with bed liner.

Oh by the way whats the best primer to apply over the por 15, Expoxy primer or ?

Thanx everyone .

Rick

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