I've just fitted the 997 standard gear shift kit into my 2004 C2 in place of the standard 996 gear shift.
Superb improvement, without excessive increase in effort or notchiness & "only" £115 inc Porsche Club discount from the local OPC.
Shift travel is reduced by a measured 15 ~ 17% ( 10mm reduction in travel between Neutral & 3rd & Neutral to 4th).
A big advantage over some of the aftermarket kits is that it comes fully assembled in the shifter housing, with no need to destroy any standard components to fit it (so if you don't like it or want to swop it it another car you can just re-fit the original).
Obviously the effort to change gear also increases by the same 15~17% - but feels OK / acceptable.
I think the effort to change gear with some of the more extreme kits could be become wearing after a while - but maybe a good way of keeping the wife / girlfriend out of the car !
I was initially afraid there may be no difference between the 996 & 997 parts as the part no. was almost identitical except for the initial part (996.424.010 vs 997.424.010).
However, looking at them both, it easy to see that the pivot is raised on the 997 version & there is a metal plate supporting the pivot which moves the cable for left to right gear lever movement compared to plastic in the 996 part
Paul
2004 C2 Anniversary
(345Hp engine, M030 Sports Suspension, LSD, 18 in wheels etc)