4 inch body lift is a bit much, just my opinion. With the 3 inch body lift the transfercase does have to have the extension welded on. If you have a manual transmission you can bend the shifter so it works properly or weld an extension on it. The automatic transmission however requires no modification to the shifter as it is cable actuated. As for the steering it depends on what year your vehicle is, I don't remember which ones have to be extended and which ones don't. mine is a 1995 and i didn't have to extend it just loosen it and pull it apart a little and retighten. The rocky road steering extension is for the 99+ model tracker and vitara. Also with the 3 inch body lift the gas filler needs to be extended and the brake prportioning vave moved a little in order to remove pressure from the rubber lines. Hope this helps.
Andrew