[Brian in Tucson]

I would compare the locations of the various electric components on the 03 to the 02. They might be the same. I put an 02 manual engine in my 01 Tip and it was just a matter of pulling the plenums off the top and switching the harness and some vacuum lines from one engine to the other. Switched the clutched alternator to the unclutched alternator, too. I ended up using the 01 throttle body and that part of the plenum system, too. On an 02 (which started life as an 00) everything lined up perfectly with the 01 components.

As far as the tiptronic connectors, on mine, there is a blue connector in the trunk that goes to a blue component. And two plugins for the transmission. & an extra vacuum switch for the other side of the trans. which is part of the engine part of the harness, I think.

Logically, I think, it would be easiest and best to use the harness that came with your car. Switch out any senders, sensors that are obviously different.