In a previous post i asked the best way to fit them on my twin axle Lunar Delta. It was sugested to fit one then use the motor mover to drag the other wheel to line up by davidnewname, well i tried it !! Got the rear wheel lined up and on went the lock , then got the mover switched on and tried to move it forward a few inches, nothing !!!!! the rollers were just spinning on the tyres, game over i thought so went and got the jack. On the way to the van i saw the problem, I LEFT THE BRAKE ON, Thick or what !! took the brake of and hey presto job sorted.Thaks Davidnewname it works a treat.