'00 should certainly be a phase 2 motor.
Slapping in just an Ej257 shortblock and expecting to run off the RS ems is going to be a big can of worms you don’t want to get into. It’s piggy back stuff on top of already finiky motors. Realistically if you’re at all planning to turbocharge this car, you need to go with a complete EJ-T swap(engine and EMS/harness) and go from there.
Believe me, it can and has been done successfully, but where cost and time are not such a factor. FWIW, I think it’s going to be just better to build a solid P2 rs motor for the car now until you can do a complete swap.
Prime example…Taylor got fed up of blowing the 30r powered P1 motor with piggy backed EMS and now is just swapping in a complete Ej257(built) with all oem EMS and harness.
There are a nightmare of head/block combinations to work with but you start getting into quench and CR talk that’ll fill up pages of text here.