caribeso

I am a newbie Outback owner, 2003 H6. I bought the car with 265,000 (yes) miles on it, but in my research it sounds like the 6 cylinders don't have the head gasket problem of the 4C and they have a timing chain that is supposed to never be changed and lasts forever. at least that's what they say. i also had very limited access to any records, so i have flushed out the brake fluid, coolant, and done an oil change of course. and then found out that it needed brakes and rotors, and upon taking apart one side, saw that the wheel bearing was bad, which turned into needing a hub too... etc. anyway, the atf fluid looks pretty gloomy and smells bad. so i have read above about the 3 change method, but nobody described it. could someone tell me what it is (do you drain and replace the fluid 3 times?), and where the heck is the spin on filter?. i bought one, but can't find the old one crawling under the car. do you need a lift to get at it? thanks