Question for fenderwell header guys/gals

So i recently acquired a 71 duster someone put a 440 in, hacked inners with a torch. What is the easiest way to fix this. Im not opposed to going back to a fenderwell header if i can find a set for a small block. Car will be a street car rarely ever see the track if ever. And will be restored but im not much of a body guy so cutting inners out and replacing is definitely out of my wheel house and budget to pay to have done...i feel like its going to be horribly difficult to patch what was cut out.

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