I'd be tempted to try ducting air from the inboard headlamp openings into hats (or an oval box) for the carbs, and use a cowl hood without the front holes.
30 years ago, we proved the deal with air sucking the mixture out the tops of the carbs on a tunnel-ram '57 SB Vette; fabricating a simple cover that blocked air from the front & back but open on the sides, using a simple flat sheet of aluminum, fixed that, but it sure was ugly.
If you can borrow an aero scoop, mock it up to determine if you can see the 'tree while staging.
Venting the hood at the rear will get rid of the air in the engine compartment hitting the firewall.