I have a 89 vette and i am wondering what would be involved in swaping the auto trans for a 6-speed, any feedback would help thanks

You can do anything if you have enough money, but a conversion to the current 6-speed is not one I would recommend. It would probably cost more than the car is worth.

You might be able to switch out the automatic for the manual that came with the car (which, I believe, was not a 6 speed but a 4-speed with overdrives) for a lot less, finding one of those in a wrecking yard.

Regardless, ultimately, though, unless you really like this particular car, you'd be better off to sell it and find a manual trans model. And again, unless you are partial to the 89 time period, moving to a later C4 would get you the six speed (I'm sorry, I just haven't paid a lot of attention to the late 80s vettes -- I was into raising kids at that time and they just slipped by me, not sure exactly when GM went to the 6-speed, I might be remembering it wrong, but I think about '92).

they went to 6-speed in 89' thats what i was asking, how hard it would be to switch one from the same year

I don't think you would have trouble, but it would be a good deal of trouble to get all the details correct. I know someone who did a similar swap on a '73 C3 and it was a lot more trouble that expected -- all sorts of little changes and diffciculty tracking down the exact parts -- I'd think a more modern car would be even worse.