Bar-end shifters on carbon aero-bars?

[stang106]

I am puting together my new Ironman distance race bike, Am using Deda Clip Black Carbon aero bars and Campagnolo bar-end shifters. There seems to be a ton of play between the bar-end ID and the shifter OD. I was wondering if I should get an aluminum sleeve machined and bond it in? Can you use bar-end shifters on Carbon bars?
Thanks,
Dave