Hi, I own a 2001 Wagon and had serious issues with overheating. To tackle the problem I had the garage exchanging the radiator wheel clutch, the thermostatic valves and finally I had them rip apart the radiator stack and clean the radiators inside. Yes, they were clogged but all this action didn't solve the problem. Since I live in the desert, I got really frustrated about it.
Finally, the garage just cleaned the electric contacts (the cheapest job of all!) and voila, the thing doesn't overheat anymore!!!!
Hope that helps.