The Tech Service Bulletins suggest drilling a 3/8" hole in the very same area to run an emergency hood release cable. I would use a 2" or 2-1/2" hole saw in the same area. If you go to most big hardware stores, they sell large dia. plastic hole plugs with a flange on one side. I'd use a hole saw that matches whatever plug you can find locally; usually 2" or 2-1/2". THen use a razor blade and slot the plastic plug so the emergency cable can go through the same hole with little air leakage.
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