Hidden Valley Auto Parts in Maricopa has a real nice 66 4 door sedan. I'm not positive it's the same (because the windshields aren't) but I think it is.
I've looked at the car a few times. They also have a 65 Grand Prix.
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1966 Strato Chief 2 door, 427 4 speed, 45,000 original miles
1966 Grande Parisienne, 396 1 of 23 factory air cars
I believe Ecklers sells the cowl for a Chev. Looked the same as my Catalina. You could check out Dynacorn. I made a channel myself and welded it in across the whole lower window channel but my corners were not as bad as yours. I used a sheet metal brake and a pair of shrinker/stretchers. Turned out great.