This could be a typical noobie move - I wanted to install a MerCathode system on my '86 Four Winns, so I went to Ebay and got the main unit that all the wires attach to (transom mounted). However, it became eminently clear that I was missing a few parts. I betcha there's more to this system than just that unit - would somone more knowledgeable kindly enlighten me? Thanks 
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