That hood-fit looks pretty damned good! Did that take a lot of tweaking/adjusting to get it there during the installation, or was it fairly painless?I understand totally, have two of my own that need attention.
Unbolt the hood hinges and remove the hood, again upside down on the work surface. Use a pencil and mark the inside edge of the surround onto the hood panel. Remove the screws, separating the parts. Now it's time to reattach the hood panel and surround into one piece. This is best done with two people and both have to work quickly. Simultaneously mix up two fairly large (half pint each) batches of panel adhesive. Apply liberal amounts to all matching seams, one person working down each side. Work quickly as you need to have the pieces matched before it begins to harden. It doesn't matter which half you put the adhesive on, just do it quickly and using the screw holes align the panels and re-install the screws to hold it in place. Clamp the edges using c-clamps, vice grips, welding clamps, or whatever you have to hold the matching surfaces together and then while the adhesive is still soft clean up the edges. After it dries, mix up small batches of adhesive and fill any voids along the outside edges or under the edges of the seams. Push it under the seam edge as far as you can with the putty knife. Clean up edges while adhesive is still soft.
Flip the hood over, remove the screws, grind a small dish over each of the screw holes and patch with fiberglass slurry. Fill the dish and push it down into the hole with the stipple brush. Refill the dish just a little bit high. Let cure 24 hours, sand to contour with surrounding hood panel. Refit the hood onto the car, adjust as necessary to align gaps. This hood now fits really well regardless of origin, some light filler to square up edges and it's ready for primer.