[Lucky]

I installed the 997 shifter in my 986 a few weeks ago, so I think I can answer your question.

The short answer is you can make the shift knob sit further aft if you desire, but it all comes down to how one adjusts the cables. You can achieve a wide range of fore-aft and left-right locations (obviously limited by the full travel of the lever in each direction). I messed with mine a few times to get it just where I wanted it. Works great -- nice and smooth and just a bit shorter travel than the original 986 shifter.