Engine, wiring harness, ECU, and exhaust manifolds or conversion headers. You might have to modify the cross-over pipe. You will need the gas pedal assembly with the sensor for the Drive-By-Wire system...or you can convert it to a wired throttle in which case you'll need a throttle body and a cable conversion. You will probably need the transmission, I'm not too sure if the 05 ECU is compatible with the 99 trans and vice versa...I'm not even sure if the 99 trans will bolt to the 05 engine. I'm not sure how the trans will bolt up under the car. And I'm not sure about the motor mounts.
You can try to find a company that offers a full conversion kit. It will probably be a costly conversion...