You have to get at your masthead to see what sort of surfaces are on top for mounting the bracket for your masthead unit. Usually there is a spot to do so. Make sure you look in the manual first to determine if the masthead unit is supposed to face forward or aft. That makes a difference and you don't want to install it facing it the wrong way. The cable is then usually run through a hole you drill on one side of the mast and it runs down the whole length of the mast to the bottom. If your mast is deck stepped, then you have to see how the other electrical (light?) cables run through the deck and do it in a similar matter. If the mast is keel stepped, then you have to see how the wires run out of the base of the mast and do it in a similar fashion. Getting the wire through your mast might have to be done by fishing a fish tape wire through first and then pulling it through. If you have a tube inside the mast to contain wires, then you can run it through it, if there is enough room left. Otherwise, just down the center of the mast and try not to twist it around halyards that might be inside. pull them tight and you should do ok. Where ever the mast sits on the deck or keel step, you will then make a junction box (which might come with the unit) where you can cut the wires and then attach them to a barrier strip so that when you take the mast down you can disconnect the wires there, rather than running the whole cable to the instrument itself. Then you must run the 2nd (now spliced) wire to the instrument head, finding a way to run it through the bilge, or under a berth, etc. to hide the wires to the unit. Again, a fish tape will help you route the cable where you cannot feed it by hand. If you have not bought the instruments yet and you have decided to not go through all of this work, then find a company that sells wireless instruments. You just have to the install the masthead unit and instrument head and there are no wires to run. Pretty quick and easy. Tack Tick is one of such companies who offer that.
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