I have a '82 320i and ever since I've owned it its had alot of moisture in the trunk. When I open the trunk, the lid is soaked. And my spare tire is always wet. My trunk seal is good and everything seems legit. Does anyone know if theirs a vent for the trunk? Or someway for the trunk to be ventilated.
Cheers.

Did you check your taillight gaskets? Those are usually the problem.