Thanks, been reading up and you can also take the wheels and shocks off so it sits flat and then put a ruler behind the rear pivot block and measure the distance to the wishbones each side as shown here.
http://forum.teamxray.com/viewtopic.php?f=101&t=18954
Had a quick look at mine and does look odd now, will need to measure... Not that impressed with the 2015 build quality so far.