Like CNY said above... just route the rear der shifter cable like so. Your 10 speed Campy stuff should shift your 9 speed drivetrain like that. Unless the parts are actually worn out this is something you can do yourself with no tools. (Ok, a hex wrench, but you likely already have that.) I've got 9 speed Campy shifters running an 8 speed Shimano drivetrain with this routing and it is flawless!