RiskyBusiness wrote:
http://cgi.ebay.co.uk/1989-PORSCHE-928-S-SERIES-4-AUTO-GREEN_W0QQitemZ230392809819QQcmdZViewItemQQptZAutomobiles_UK?hash=item35a47b495b
Owner lists modification about halfway down the page.
To be picky

, it says that Paul Anderson noticed that the modification had been done, not that he did it himself. However this suggests that he could probably give you a better answer than the rest of us.
My thoughts are that if it can be done with the S4 box it can be done with the S2 box, but why would you want to? Porsche obviously designed it to start in second for a reason, perhaps because they though the majority of owners wanted to pull-away in a controlled and refined manner, in keeping with the noble character of a man (probably - it was the late 70's) who could afford a new car that cost more than the average house, rather than in a lairy, wheel-spinning/tyre smoking manner, reminiscent of a boy racer
If you do want to start off in first gear, that option is always available by moving the selector away from "D" (or if you really boot-it when the selector's in "D" the box will change down to first) but, unlike the car in the auction, the majority of S2s do not have an LSD and the standard 7" tyres are relatively narrow, so starting off in first gear will require a bit more finesse.