Hi King_Cod,
I have thought about a radar arch or super structure what ever you want to call it. And I think one day I will either buy one or make one. In the past I have heard a bit on this site about what other people think and the one draw back is having your spare rods in the holders while your trolling and when you catch a fish the spare rods are pointing right into where your trying to play the fish and your spare rods get in the way.
Just don't put your rods in while your fishing, install a radar, install lights facing forward and backwards, Great spot for antennas, You could even put on a radar reflector for those real foggy days. Let us know what you end up with and what you mount on it ..... Steve.
And remember....Keep your tip up!!!