Not sure if 996 is the same with regards to valve/piston clearance etc? but I had my 916 heads skimmed by 1mm. Cams needed re-timing and a larger idler pulley to get belt tension back but, along with head gasflow work, it livened up the engine up somewhat. Every cloud has a silver lining and all that...
IIRC the standard 916 pulleys are black and the larger ones I have fitted are gold coloured and were originally fitted to a different model, they are 2mm larger I think? I got them from Chris at CJS, who also did the skim and flow.
Quick update on what's happening with my engine. Seems it was cheaper to put a whole new engine in that putting new heads, and cylinders on. So I've now got a same year engine going in with half the kilometres on it. We are in monsoon here now, so not overly in a hurry to get it back.
All sorted, back on the road and purring like a kitten. Absolutely fabulous, and now have a complete spare engine.
