Will this tank mount using the factory attachment points?

Yes. It bolts directly to the factory mounting locations with no drilling or brackets. Just unbolt the old tank and bolt this one in its place.

Do I need to drain the cooling system to install this?

You'll want to drain coolant from the old tank before removing it to avoid spillage. Use a catch pan and dispose of it properly. The new tank installs empty and refills from your system.

What's the difference between aluminum and the original plastic tank?

Plastic tanks become brittle over time and crack under thermal stress. Aluminum won't degrade, resists corrosion, and handles repeated heating and cooling cycles without failure. It's a permanent fix, not a temporary patch.