Mike, I will have 4" x 8" braces at 45 degree angles both directions of all 4 corners. Are you saying the thread rod mount is best? What diameter and is one per post sufficient? I've only seen 3/4" diameter available at hardware stores and the big box stores. Also, what size washers for the nut mortise? If 3/4" rod is used, I've only seen about 2"OD washers. Is that enough? Is an epoxied rod better than a bracket imbedded in the concrete? I don't think I need more than the epoxy rod/stand off connection but for my own education, what is moment connection? Is that available prefab or is it cheaper to have something fabricated locally? Unfortunately, I am not a welder and will have to hire any such fabrication out.