Automatic Shifters?

Anyone tried to replace their stock Shifter with an after market one? How Difficult is it?

Also, what's a good piece to replace one with?

its not that hard just unscrew the 2 screws that are on the front of the nob, unplug the o/d under the center consol, (easier if you cut it then splice it back together ;) then pull it off!! just did that on a friends GS 3 days ago!