You can get the arb out through the back of the subframe, undo drop links and pry the to retaining plates apart enough to slide arb through. I fitted H&R arbs which are alot thicker and still managed it didn't have to lower or slacken bolts on subframe. Best to get a mate to help as its fiddly as hell. If you need other info give me a shout. But you need an arb (even if its a stock one).