I am on my second set of tires.  The front tires keep wearing on the inside. The ball joints seem ok. I found a bushing on the sway-bar that is bad,but I do not see how this could be my problem.  Any suggestions?  

Sounds like you have a serious alignment problem with your front end, particularly a caster/camber issue. I suggest you bring it to a qualified alignment specialist and have the entire front-end checked out and aligned.  

Inside tire wear on front & back of C5 & C6 is very common if aligned with factory specs
Lloyd