Do I need to flush the refrigerant system before installing this condenser?

Yes. Always recover the existing refrigerant properly before removing the old condenser, then flush the lines and receiver-drier before fitting this unit. Old debris in the system will damage your compressor.

Will this condenser mount using my factory connection points?

This is designed as an OEM-equivalent replacement, so yes — it uses the same mounting locations and line connections as the factory unit. No modifications needed.

Does this come with new O-rings and seals?

The condenser assembly itself ships complete. Grab a new set of O-rings and a receiver-drier when you order — they're wear items and should be replaced during any AC service.