I picked up a Raymarine i40. This instrument is compact and gives both depth and speed. It comes with two thru hulls. I found that they are very similar two the originals from 1985. Over the weekend I installed them using 3M 5200. I ran the new leads by tying them to the old ones and pulling them thru to the back of the boat.

The autopilot you see here is long gone I installed a new Raymarine smartwheel . The computer is mounted inside and a seatalk cable runs to the instrument which I had mounted offset to the left up top. I had a chart GPS hovering over all that mess. 
It is very hard to get around those giant pods and the wheel. 
The plan is to build an enclosure that is centered over the compass. It will enclose the two Raymarine instruments with the map GPS over the top of it. The two pods will be removed and the plate they sit on will be machined away to increase the ability to get around the wheel.