Later revisions will plug in to the ecu but the wiring mapping is different between generations. The pins will go to different places, sensors, etc. Take a look at the ecu diagrams at http://gt4.mwp.id.au
to see the differences.
This could be quite a large undertaking if you are uncomfortable with wiring.
The closest harness would be from a st185 but you will have to deal with the intercooler differences at a minimum.