Just mount it to the windshield. Unless you are going concourse. If you get it wrong it can be moved by heating it the glue will release. I have moved mine a couple of times with no problems.
Ron, The Computer Greek I love therefore I am. 1954 3100 Chevy truck In the Gallery 2017 Buick Encore See more pix 1960 MGA Roadster Sold 7/18/2017