My 2003 S185 creeps ahead on the right side. The steering levers won't centre properly. Any adjustment I make only makes it worse. There is no apparent wear on the linkages, only wear on the linkage stop blocks on top of the hydrostatic pump. My dealer tells me that this a complicated procedure that requires it to be brought to their shop. I am a fairly accomplished mechanic and do all my own repairs so I should be able to handle this. Any thoughts, tips, pointers?