Edson wire run.
My own pedestal already had a wire out the back(forward) for the GPS. I first purchased several sizes of rubber grommets at Lowes before deciding on the size of the hole. I drilled a second small hole on the forward facing side, just lower than the other hole. I used one of those heavy rubber 6" couplers from Lowes plumbing. It came with better stainless clamps than the Simrad ones. I cut out a vertical section so that it perfectly fit around the pedestal. It provides a much better clamping surface. But you have to fit the clamps first so you know where to drill the hole, either above or below the clamps.
