It looks like if you raise the grille a little, the headlight bezels could be moved out slightly to fit a little closer.
First, I think you should get all the nuts & screws in place on the grille, upper & lower moldings, and headlight bezels, then see how it all fits. I'm curious if the outer screw holes on the headlight bezels line up with the plastic barrel nuts on the fenders. Also, I found that the replacement plastic barrel nuts don't match the originals, and needed some trimming & shimming to work correctly.
My 68 now has the original header panel & lower valance, NOS front fenders, NOS grille, NOS headlight bezels, and CHQ upper & lower moldings. There are gaps of varying size all the way around the grille & headlight trim. The gaps vary from just touching to pretty good size (never measured them, but could be 1/8" to 3/16"). There were originally some good sized gaps on my car as well. The varying gaps really bothered me at first, but now that the car is done, I don't even notice it.
The gaps on your car look fairly consistent all the way around, and IMO it looks pretty good.