With an ethernet switch you can share your gps wherever it is located.  I have 1198 - console, 898 bow.  The puck for my 1198 is on transom gunnel almost directly over transducer for more accuracy.  I moved the 898 to bow but kept puck on console.  Only about 4' difference.  The gps for the  898 was hooked to my vhs radio and I saved by not having to move all that.  More of a personal preference rather than a necessity.