So I need to get BIG FRIG ready for Patriotic Protest rallies up here in the hinterlands. I'd like to be able to put a big ol' PA speaker in the bed on occasion to pump the "God Bless the USA" and "Brought to you Courtesy of the Red, White and Blue" to the surrounding masses. So can this be done by wiring something from the radio and have it "plugged" for use when I need it? Thanks for any ideas.