I have a similar problem to you, but i have the old style bar. I printed out a copy of the diy ARB replacement instructions by VKX245l, with the parts required to do the job. I took this to a local VW/ Audi specialist.
They told me that there is no need to change the ARB, but instead to break off the old plastic housing from the ARB, and fit the new modified bushes and clips.
I pick up parts tomorrow, and the A2 is in on Monday for ARB, Cambelt, Brake Pads and service. I`ll let you know the outcome.
Phil