Fairly easy to do once you have done one and know what to dismantle & how. Unfortunately, too many instructions needed to take some one step by step on a limited space forum like this. Try a Google search for a repair manual. Cost of bearings & seal kit here in NZ approx. $45- $50 NZ. Don't know where you live so can't say how much it will cost you. An experienced service person should be able to do the complete job on a Smartdrive in 1.5 hours. If you where here in NZ I would charge $150 complete job with pick up & delivery after.
Lincoln Appliance NZ, October 2011