I've been thinking about a single beam. I have a couple of 4 x 4 x 8 oak posts and it's hard enough to lift those very high. I don't see being able to handle a 4 x 8 x 14 to a height of 8' without some kind of machinery. I could do it one end at a time and place scaffolding to support it. But then I'd need some kind of specialty hardware to anchor, or I'd need to notch the posts.
Plan for now is as shown. 2 x 8 headers on each side of the posts. Center post would not normally be there, but could be installed if we get a heavy snow forecast. Fill between the headers to support on top of the temporary post might be a couple of pieces of 2 x 8 or 4 x 4, whichever I have available. This way, I can use more standard brackets and timber screws or nails.
I can use my normal method of ratchet straps to lift each end of the headers into place so I can drive anchors.
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