It's been done before in several GNs. I think you have to notch the inside of the buick console to get them in there. BuickGN.com makes a custom top plate that fits the buick console. Besides the shifter itself, you will need the cable and bracket that mounts it to the pan rail. I "think" the arm that bolts to the shift shaft of the trans is the same, and i've been told that you can cut and reweld a stock lower cable bracket (the one that bolts to the trans pan rail) to make it hold the cable in the correct place if you need to. A buddy of mine parted out a badly wrecked/rusted 84 hurst olds and I removed the lightning rods and sold them for him on this site. Was asking $750 and he told me to let them go when I got a $650 offer, so I did. I sold the shifter, mounting bracket, top plate, cable, cable bracket for the trans, and arm for the shift shaft.
Personally I think they are overrated. They sure do look cool, but they are kind of quirky, and you have to push those damn buttons down ALL THE WAY before throwing it forward into the next gear or it will not go. Not the kind of thing I want happening when my car is at redline. We concluded that you could go in and grind a taper on the detents of the mechanism so that they would slide forward without pushing the buttons if you planned on racing with them. I could have had those in my car for $500 or less with some trading, and I chose not to use them.
Anyway if you go ahead with it, they do take a special cable and bracket for the trans. unless you like to fab stuff, then you could most likely pull it off using only the shifter. Hope this helps.
bob koch