You have to cut down (unless you have a DD lite) the outer nubs on the DD side, and you need to dremel out the adjuster holes for the rear axle so it can slide back more. When the track is new you can do it without dremeling but as it stretches you'll need a bit more adjustment. (ok, edit, I'm a dumba**, 162-162, ignore the dremeling part!)
It's pretty easy, just time consuming.