There is a company called BattleAero that has a chassis mounted swan neck wing that still allows use of the trunk. They fold the wing down and away from the trunk, obviously not the easiest way to use a trunk but it's an idea. I like how their wing looks and they have options for endplates as well, but there is zero research into performance and they provide literally nothing to state it aids in any kind of performance. But just an idea.
Edit:found a picture
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