Evap vent valve clogging

Got a PO446 code on my 2001 Tahoe and it turned out to be the Evap. canister vent valve was clogged with loose dirt. This seems to be a design problem due to its location and the poor filtering with the valve. I saw a 2002 tech bulletin that described a new valve for pickups that had an improved filter with a easily removed cover for cleaning. Mine was a pain to clean, as I had to completely remove it from the vehicle. I drive on many dirt roads in Idaho, and this looks like it :confused: is going to be a regular thing.
Any one know about this problem, and if a fix is available? I am out of warranty, and my dealer was no help with info.

Joe from Boise