How to replace sensors

I have a 1997 mercedes s420 with 128,000 miles and the dealer says fault codes are for steering angle sensor and yaw rate sensor and both sensors need replacing. I need to know location of these two sensors, part numbers of each and how to replace these sensors in my own home. I'm fairly mechanical and need to know exact process for each. Dealer quoted $3,670. I found on e-bay a yaw rate sensor part number A-003-542-87-18 new for about $50.00 and need to know if this is the unit that I need. Will dsomeone have to reset codes after installation of replacement parts?