I was even thinking magnets inside on the hood slipper concept.
Sticks to hood, drapes down half way to ground on front and sides. Then, second piece goes under engine, push it under car with a small push broom handle and it would have flaps to come up and meet the flaps draping down. At that point, bungees, Velcro, hooks, whatever, can cinch the 2 halves tight.
Almost like 2 soft sided insulated clamshells to cover it as tight as practical from the windshield forward.
The top piece would be tarp material one side, flannel on the other. The bottom piece would be aluminized tarp, since it would be up against hot car and dirty ground while installing.
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