Cars rely too much on a well charged good battery to work properly. I would buy a new battery instead of trying any type of fix even if possible. Not worth it. I use the best batteries, tires and brakes possible.
Uhhh, please read my initial post ! It's not just a "harness post". It's the battery terminal. Not only that it's the positive or hot side. Don't cheap out. Get a new battery . Next time be careful or get someone else to do your maintenance.