[Dave at Pelican Parts]

Yup. Synthesis, I would seriously consider adding the flaps back in again.

If you are getting your fan air from the front of the car (e.g., by way of the "sewer pipe"), cut off the parts of the engine tin that go over to the engine shelf. Plus the rubber seals. If you get your cooling air from the front of the car, you don't have to worry about re-ingesting warmed air.

--DD