Look up "Shiftmate". There are models that will let you do nearly any mix-and-match between Campy and Shimano components. I've used them to match Campy 10-speed shifters with Shimano 9 and 10-speed cassettes and rear derailleurs and Shimano 10-speed shifters with Campy 10-speed cassettes and rear derailleur. Nearly any permutation is possible and they work very well.