Taking the example from Walrus, I wanted to take it one step furthur for the ease of filling it with water and to make it a little more secure.
The terminal box is from just about any DIY hardware store. I purchased all my materials from Marshals on 8423 Production Ave (at Miramar Rd). They have every bit of hardware you will need, from Termial box to stainless hardware and stainless/rubber washers.
Purchase your terminal box so it is just big enough to hold your ducer. Accuracy in drilling the holes is crucial to maintaining a parallel ducer install, both left and right, and up and down so the ducer sits parallel to the bottom of your yak.
I wanted an easy way to fill the ducer holder with water, so I drilled a hole in the sail mast. This enabled a refill at any time (although I have noticed "0" water loss). The terminal box sits right against the sail mast, so the mast also serves as something stable to secure the terminal box against.
The initial results are great. I can following a jig all the way up/down past 100', and watch it as it sits there 10' above the bottom : )
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The ducer sitting in the terminal box
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The sail mast removal
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The install
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The final product
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