1982 old? That's new, when it comes to C 152's! Are you ever lucky to find such a new one to learn in (doesn't mean it's the best though!) Earlier years had their charms too! Surely you can't think an aircraft "old", when it's only two years older than the Space shuttle you sent NAStornauts into space in!
There are a lot af charms of Cessnas. One of them is that when fuelled to full, and parked at all on a left wing low surface, they are going to vent fuel. There is a vitally important fuel vent flapper valve inside the tank, coneected to that dribbling vent line. It let's in air, so as you use fuel in flight, air can replace it. There are also vented caps, but they are imperfect. To be extra sure, there is a small hole in the flapper of that valve, which air can flow in through, ans gas out. Don't let it worry you....
Stop drills on corregated skins in most areas are not worrysome, I would be very surprised if you saw a stop drill on a fuaselage skin, other than the non-strucutral plastic fairings here and there.
I'm sure you will come to know and appreciate the 152 for its glory. They're simple, but like any aircraft, there's lots to learn about them!