I know there's a solution to my problem out there and I don't want to have to go to a body shop to do what should be an easy fix.

Problem: Rear of hood (close to cowl) sits too high by almost 1/2" on both sides. The front of the hood is flush with the fenders, and the gaps are correct.

Theory: I'm going to suggest that when these cars were assembled there was a group of 3 men attaching the hood and ensuring it fit properly. 2 that attached the hood to the hinges and one that helped with the rear hood positioning. Somewhere (can't remember where and I've done searches on this) I recall that if someone holds the hood upright, while another person loosens the hinge to fender bolts slightly on both sides the hood can be properly seated by pushing the hood fully up as far as it can go while the bolts are quickly tightened. The theory is this will suck the back of the hood down level with the fenders and matching trim. Is this the correct way to solve my problem? I have access to a warm body that's extremely tall and could help, or a properly wedged 2x4.

 

That is how to adjust that height...with the hood up.
The springs and hinges need to be good, lubrication helps too.
I have had to elongate that adjusting hole in the hinged to get more resolution on the adjustment. Which requires hood & hinge removal.

 

The hood and hinges were removed when the new replacement fenders were installed. But they're NOS OEM fenders so the fitment should have been spot on. So likely just need to take the plunge and try that process I guess.