I've got a scanner "mounted" in my ST as well... it's just a handheld mounted in a "radio shack" cell phone holder. The holder has a small disc that attaches with double-sided tape (the good stuff, like the 3M stuff for vehicle badges), then a holder that attaches to that disk via a suction cup with a flip lever. The scanner just sits in the cradle, and the sides press in to hold it. I've got an external mag-mount antenna on the roof with the cable routed into the cab, and it's hard-wired for power.