J-Spec Sweden

Hi! Im just about to do this conversation on my aristo (probably swedens first aristo tt). I have some contact with a guy from UK who has this conversation on his car, but unfortunately he havnt recieved it from Japan yet. I know that there is lots of bits to change/put in, but do you really need a custom tailshaft? As im gonna tune the car quite alot after the conversion im thinking about buying a cusco LSD or something like that, but do i need to custom-make the shafts? Still searching for a gearbox...