Will this tank fit my cooling system without bleeding air or flushing?

This is a direct replacement tank, so it mounts to factory locations. You'll want to transfer your existing hoses and clamps to the new tank to maintain your current coolant charge — no system flush needed unless you're doing preventive maintenance.

Do I need to drain coolant before swapping this in?

Not necessarily. You can disconnect the old tank and quickly move the hose connections to the new one, but have a catch pan ready for minor spillage. If you want to avoid mess entirely, drain the system first.

What hardware comes with the tank for mounting?

The tank assembly ships as-is — check your service manual for the correct fastener specs and torque values for your model year, as mounting hardware specs vary by production batch.