Doug Kelly...I've taped mine to the back window of my canopy, has been no problem. 2 nd part of your question...I just called WDF, Montesano office, the gal told me "in Pacfic County, enforcement will look for the sticker", so maybe the back window of the pickup would be the correct place. I have the same problem.
Edmund.....Like your idea, hang on the "rear view mirror", seems to be ok where my wife works for parking...very easy to check. State, WDF, probably wouldn't like it cause someone might "move it to another vehicle".
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"Worse day sport fishing, still better than the best day working"

"I thought growing older, would take longer"