I'd guess run extremely rich. As for the pitted pin. That's a little wierd. Where was the pitting? Between the bearing and piston?
The majority of the pitting was near the outside edge (but not limited too) of the bearing cage. I will take a pic, and post it up (hopefully you will be able to see the pitting). I have seen rust pitting before, and this doesn't really look like rust, it looks like lots of tiny pin holes.
Its proof to me my '01 bike was barely ridden by a timid previous owner... my bike still had the factory Vasoline style grease in the linkage (and in clean condition!) My bike still had the original green carbon steel bars, (and only slightly bent!), and finally STILL had the original sprockets! (Thats the PROOF)
The crank looks perfect, so it should be all back together tonight. I can't wait to rip my 5 with the new thin "race" head gasket. The new one is .008" thinner than the stocker.