Ultra High Performance Boats

Below are a couple of ways to mount a GPS antenna under the dome of a XB-2003. 

 
Here the antenna is mounted in some foam. Marine RTV  was used to anchor the antenna to the foam. Tie wraps are then used to mount the antenna to the steering bracket. (Kevin from FL®)


Here a piece of diamond plate aluminum was cut in a strip about 6-8" long and 1.5-2" wide. Once cut and the edges smoothed it was bent into a "L" shape at a 90 degree angle. A hole was drilled in both ends, connecting the GPS receiver to the long side. Behind the dash, the nut holding the depth finder bracket in place was taken off, the short end of the fabricated bracket installed and the nut retightened. (Texan)


Here the antenna is mounted on the starboard side of the floor under the XTB-21's bow. (Blue Gray in PA)