I installed a second antenna for the Raymarine Weather Module (larger mushroom dome on the right) over the weekend. The smaller antenna feeds the separate stereo receiver. They are both held down with 4200. My intent was to keep them off the stern rail and out of the cockpit, located somewhere with a clear view. I discovered that by removing the light in the overhead directly above the nav station just in front of the aft head bulkhead, you had access to the bottom of the cabin top. The wire feed runs right down between the windows into the back of the panel. With a 9/16" hole drilled thru the connector feeds down with enough length to allow you to connect it to the longer cable. I fed the small end down thru with a stiff wire and was able to pull the second thru easily. The extra length is coiled and zip tied up between the liner and deck should it ever be needed. You can buy a splitter for the antenna if you like but the weather receiver comes with an antenna in the box (the base and trim screws off) and the splitter is about $100 delivered.