I'm planning on running classic production so I can't really rake the windshield back any farther than GM did on the G-body. Here's the panel area that would be missing (the welded in plate on the cowl:
Here's the heater box that was deleted from the above pictures (needing the bare metal panel and the black welded in piece):
I'd basically convert that screen section to the intake.
Looking at old NASCAR flow diagrams, it still looks like the base of the windshield is still a high pressure zone:
Now the one thing that makes me wonder is that since the car has a gap between the hood and the windshield, will that recess be under positive or negative pressure? This image I found, in which I'm assuming that the car has a similar windshield to hood gap like most modern vehicles, shows a much lower pressure area at the base of the windshield:
Someone borrowed my rulebook but I remember something in there about you can't put the air intake any lower than it was from the factory. Am I remembering correctly?
Any further discussion?