On second thought, maybe you can salvage this by laminating some treated 2x8's or 2x10's along the length of the horizontal beams to tie them all together and straighten them somewhat, and adding some massive braces. Laminated beams (and braces)are almost always better than single ones, and tend to warp less IMO. A beam made of three 2x6's will usually be much stronger than a single 4x6, and maybe not cost much more.
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Observing since 1966
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