You do need to have a template so the beacon is properly facing when mounted. Mounting a beacon takes a lot of time, but it isn't that difficult. The time is in getting it properly located. I don't know if the stud spacing is the same as the Model 17 series sirens, but if it is, then Ed Renstrom has the template, and I am certain that he will share it with you. I use threaded 1/4" rod, flat and rubber washers, and a bunch of nuts to make my own studs. I usually make them longer than needed, and trim them to the proper height once the beacon is located on the roof. Just make sure that there is a zipper under where you want to mount it, and that you can get power to the beacon before you start the project. The beacon should be wired with 12 gauge stranded copper wire. When you are ready to start the project, let me know, and I can give you full instructions on how to do the job with minimal effort. The first one is always the most difficult, and the more you install, the easier it gets.