I went to Harbor Freight Tools yesterday and bought this air gun extension rod for $4.00 and it worked great at blowing the road debris out of the radiator fins. This extension reaches all the way back through the radiator grills. I will definitely be cleaning these radiators on a regular basis now since these radiators inlets are basically street vacuum cleaners.
Hopefully it doesn't harm the radiators. Did this with a power washer once and never again, bacause i had to buy new radiators.
I my opinion best way is to remove the front fender and inner parts and clean the radiators with a vacuum cleaner. Also if you have air condition you have to remove the air condition radiators to get the dirt out between air condition radiators and water cooler radiators.