I got the shifter gaskets from here...
I used the base gasket... it looked almost exactly like the stock gasket that was on there. I did remove the small gasket that was on the underside of the GMM Shifter.... did it with an ice pick and a small flat head. Careful though its easy to slip with the ice pick on the gasket cause its super glued in...
As far as the two smaller shifter handle gaskets... I was unable to get them on because when you slide the square base on the bottom of the upper shift handle... onto the actual shift lever... its a very tight fit and the gaskets wouldnt fit without getting all squished... thus I couldnt get them to line up correctly and fit right so I left them off.
I still have them so I may screw with putting them on later. I was frustrated and at that point all I really wanted was the shifter... didnt feel like screwing around with these two lil gaskets that were getting squished and not lining up with the 2 holes that secured the whole thing together. You could easily try and put them on later though in like 5-10 mins with a small ratchet, all from inside the car. Im thinking of using some kind of lubricant to get the gaskets and everything on correctly without being all squished.
Personally the noise doesn't bother me... nothing about this car can really upset me I love it. I bought the shift gaskets cause they were very cheap... and I'm sure they help a little. If I took the time to correctly install the smaller shift handle gaskets Im sure it would cut down alot more on the noise because theres nothing to stop the vibrations from cumming up from the tranny all the way up the shift handle... except that one base gasket.
I would advise you to get some high flow clutch stainless lines and remote bleeder line... and replace your tranny fluid with a good synthetic like Royal Purple Synchromax or Amsoil....
Heres some links that Ive saved for later on when I replace my lines... as far as what a remote bleeder is I'm not totally sure.. I assume it just makes it easier to bleed the clutch. I dont really know exactly where to find one other then the link below... that I found from doing a search on the forum.
SS Clutch Line
Classic Tube - Product Search
Remote Bleeder Line
Ask for Jeff Creech (919-680-3966)
Carolina Auto Masters
Got these two links from here...
and I have these because I bookmarked them long ago...
Solid Clutch Hydraulic Line for 04-06 GTO (GTOHYD) - $89.99 ..
McLeod Universal Billet Slave Cylinder Assembly (T56) - $379..