How do you change the spark plugs on a 1999 Subaru Legacy Outback?

For the LH side remove the screen washer bottle (two screws and two hoses). For the RH side remove the air inlet ducting (two screws on the radiator crossmember, a bolt and a nut secure the rest of the ducting). Remove the plug leads by pulling on the lugs, not the cable. The plugs are best removed using a 3/8" drive 5/8" (16mm) spark plug socket on a 6" (150mm) extension, and a ratchet.