Some light rubbing compound will take that off no problem.

Just keep rubbing until it starts to come off, then STOP. You don't want to overdo it on the first shot.

Once you have taken off most of the outline (ie. stop at the point where the outline is still barely there), wipe off and polish the trunk lid area you are working on. Then carefully look and rub with a much smaller amount of compound, in steps until it is all gone (wipe off, rubbing compound, wipe off, examine, repeat..)

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