Hardy Boys 43: the Mystery of the Aztec Warrior

The handwritten will of a deceased world-traveler is strange and mysterious. Its cryptic instructions are to deliver 'the valuable Aztec warrior to the rightful owner, a descendant of an Aztec warrior.' What is the valuable object and where is it? What is the name of the owner and where is he? Frank and Joe Hardy have only one slim clue to work with: the name of a complete stranger who can help find the answers.