How could Nephi and his people build a temple "after the manner of the Temple of Solomon"?

Other Israelite temples were known previous to Lehi’s day. In 1960, archaeologists discovered the remains of a small pre-exilic temple to Yahweh at the site of Arad. This modest structure was built after a similar pattern of Solomon’s temple with a sacrificial altar in an outer courtyard, an enclosed central room with two incense altars flanking a small inner chamber which functioned as a holy of holies. This structure could easily have been constructed by a dozen men in a relatively short period of time.