Shift linkage question
 

I am looking at a Z28 M6, and to be honest i dont know a lot about transmissions. Ive worked on pretty much everything but them.

This is what the guy says:

"the other little flaw is that 3rd and 4th shift linkage or boot is wore. i replaced all syncros w/ carbon fiber kit. its not the syncro but the boot that guides in the gear. i saw they had wear when putting the syncros in but didnt have enought money to get them at the time of the synco rebuild."

What exactly is wore and how much would parts and labor be? How hard would it be to fix myself? Or could i, seeing as i only have a small floor jack.

Any info would be appreciated, thanks.