I think we have a resident Pro on here in Big River Marine. I would take a chance on splicing the transducer people have done it before with success. The livewell problem may be hard to find since it is intermittent. BRM said in another post to make sure the pump is not getting gunked up. I'm not sure what you mean about breaking the rear sonar, is it a physical connector on the head, or the transducer? Sounds like you and Zettler had about the same run of luck. You can take a look at his post in the electronics forum.
Hope you get it worked out and are back fishing soon.
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