I have fixed many of these. The damaged metal with the nut cage must be cut out of the hood stiffener. I rebuild the nut cages, and rivet them back onto the metal plate so that the nuts move as required for adjustment. Next I cut a new piece of same gauge aluminum to fit the cut-out. The slotted holes are made from a pattern and the re-built nut cages are riveted back in place as original. Next the assembly with the new aluminum is installed in the cut-out and butt-welded in place. After finish grinding and sanding the surface is all original metal with no fillers or visible welds. Sounds very complicated, but with the correct welding equipment and fabrication experience it is not that difficult. It takes me about 1.5 hours a side. Make sure your welder works from pattern made from a good hood so that the holes are in the exact and correct place.