Thanks for the comments and suggestions, some things I have not thought of before. Such as if I pull 4� of muck out where does it go. That�s 8 acres of muck 12" deep. I like the idea of raising the dam but it�s not feasible since the water would back up into the neighbor�s driveway.
As for the trees on the back of the dam I�m going to leave them for now. I think I may add about 3� to 5� width to the inside of the dam so that should help with the root issue. I have an arborist scheduled to come out in the spring and it will be one of the questions for him.
As for removing fish, a friend at work is a Scout leader. I asked him if his troop might want to help out with that. A couple dozen young boys with fishing poles could put a good dent in the LMB over a weekend camping camping trip in the spring. BG will be catch and release. For now I will start the log.
Bocomo, the link to your pond thread has given me a good framework to follow myself.
Thanks everyone.

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