Madbajan, Befow, are the part numbers you will need to upgrade your 03 Yamaha to the 04 starter configuration. Prices are retail in the USA. 5TJ-15498-00-00 COVER ASSY 2, $31.83 5TJ-15560-00-00 WASHER, $223.99 90201-105A8-00 WASHER, PLATE, $3.65 (2EA REQUIRED), 90380-10002-00 BUSH, SOLID, $.76 These nomenclatures are directly from the Yamaha parts catalog and must lose something in translation from Japanese to English. The $223 Washer is the Torque Limiter Gear (it comes with the gears and the axle shaft, DO NOT order the axle shaft separately which is possible). Install the two "Washers, Solid" with one on each side of the "Torque Limiter Gear". Tap the "Bush(ing), Solid" into the side case until it is flush with the inner surface. It is split and does not require the heating/cooling technique usually used to seat press fit bushings or bearings, just tap it in with a soft hammer or hammer and a block of wood until flush with the case inner surface. You don't need a new O-ring for the "Cover Assy 2", just use the old one from the original cover. You DO NOT need the L/H Side Case Assy 5TJ-15411-10-00, $92.49 as was specified in a previous post. The bushing you will purchase for under $1.00 eliminates that requirement. Some dealers have had a hard time finding the solid bushing in their index--- be insistant--- the part number above is correct and the part is available. If need be, shame them into looking harder by threatening to go to a dealer that knows what they are doing :.) If you are slow and take time to inspect the entire job, it should take all of 10 minutes. I think that this update is an absolute must for peace of mind. My woodruff key has been loctited, but the update is the answer to eliminating the chance of shearing the woodruff key in the future. If you have trouble getting parts, Motoworld of El Cajon (near San Diego, California) can't be beat!!!