This is all just a guess. I did a Honda once and it was a lot easier than a Boxster...
A quick search of here, 6Speed, Rennlist, and Renntech will give you the best advice: Sell the car, Buy a Tiptronic. That same search will probably not yield any 'build threads' of people who have completed the task.
If you insist and persist, you will probably be best served by having a wrecked Tiptronic car to swap parts over from.
A few quick thoughts:
Needs: shifter & linkage, cluster, engine/transmission harness, matching set of ECU and TCU & Central Locking unit, Steering wheel, Pedals, Transmission cooling lines, Heavier springs (per stock configuration), Belly plate, mounts, and probably lots more good-to-have stuff like venturi hose to brake booster, heavier starter & alternator,...
The engine harness from a Tiptronic car will have most of the needed wiring integrated. Other thoughts on wiring: Shifter interlock - maybe re-wire from clutch switch, steering wheel wiring, probably add a few ECU to cluster wires.
The worst part of the Honda swap was pedals. hard to reach, hard to wrench. Mine was actually auto to manual and I suppose you could leave the legacy 'third pedal' in place. ...No, not for a 'wife's car'.
Don't Do It. But if you do, please post it all here, with pics.
