Figueroa worked closely with each of the more senior archaeologists, including climbing the 900-foot (270-metre) volcano Rano Kau with Ferndon, supporting Heyerdahl during negotiations in which Chilean authorities threatened to confiscate all of the expedition's archaeological materials, excavating reed huts with Smith, and conducting excavations on the islands of Hivaoa and Raivavae with Skjolsvold.
Ferndon recounted how a "grim and bearded Gonzalo" showed the other team members "beautifully excavated" terraces "standing clean and neat as if recently swept and dusted", and Figueroa's and Skjolsvold's "work output was certainly in excess of what one would normally expect.
Many moai had been pulled down during warfare between rival island clans, and erosion, resource-scavenging by natives, souvenir-taking by tourists, and encroachment by public works were destroying what remained.
Each statue was over 4 meters (13 feet) in height and approximately 15,000 kilograms (33,000 pounds) in weight, and was raised by gradually levering it into an upright position, just as the prehistoric islanders had done.
Figueroa and Mulloy considered this "a pilot project to demonstrate that ahu restoration could be done at reasonable cost and that it should be an important part of a future program of conservation of monuments.
The team also included Charles E. Peterson, an architectural historian, restorationist, and planner, and Raul Bulnes, an architect from the Chilean Ministry of Public Works.
In late 1966, Figueroa and Mulloy co-authored the resulting comprehensive UNESCO report "as part of a wider investigation leading to a general development plan for the island of Rapa Nui.
"[11] Figueroa and Mulloy asserted that "[b]ecause of the remarkable number, size, and variety of the archaeological monuments on Rapa Nui, there is no other island in the Pacific remotely approaching it in adaptability to be developed into an island-wide museum of Polynesian prehistory.
This could be accomplished by a relatively modest long term project of archaeological conservation and restoration ... [S]uch an island-wide museum ... would quickly become world famous ...".
In the 1980s, Figueroa returned to Rapa Nui with Skjolsvold to examine the kneeling moai, Tukuturi, and to excavate what was believed to be the location where Polynesians first arrived on the island.
[15] The University of Chile opposed having an American lead the restoration, and named Claudio Cristino, the director of the Easter Island Museum, as the chief supervisor.
[15] Figueroa also argued that the restoration team should include a larger number of trained archaeologists, but the University of Chile sent graduate students to assist Cristino.