Working on what i thought an easy part of the task... swapping gps puck out for the new unit. I thought i could just tie a rope on pull tje old out and the new in. Graph is mouted on starboard at the console. Seams the cable is for the puck is some how run through the port side tube but it does not come out up front... it is a z520. Any one have any ideas? I assume i can not use the old puck here and need to get the new o e with heading sensor installed.