BTM, I have a Milwaukee Deep Cut portable band saw. It will cut 4-1/2" square tube. You should mark the piece to be cut with a square on all 4 sides. I could cut it for you in a day or 2. I've made a million cuts with these. It helps if you have experience.
I don't know what your boat weighs, but I would weld the tongue on.
Artie
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Artie
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