Will this radiator work with my transmission cooler lines, or do I need to reconfigure them?

The transmission cooler is built into this radiator. Your existing cooler lines connect directly without modification—they're designed for this exact setup.

Do I need to flush the cooling system before installing this, or can I just swap it in?

Flush the system first. Old coolant carries debris that'll clog a new radiator fast. Takes 30 minutes and extends the life of this unit.

What about the hose clamps and water pump gaskets—are those included or do I need to source them separately?

Radiator assembly only. You'll need hoses, clamps, and gaskets from your parts supplier. Recommend replacing them while you're in there anyway—they wear out with the radiator.