Anthropology is a large field with many specialities. First you need to figure what path down Anthro you want to take, whether it be linguistic, archaeology, cultural, or otherwise. You did indicate archaeology. Next, get a listing that lists schools that offer your Anthro field. Choose the ones you are interested in based on potential fit, then look at their admissions requirements.
If there are further questions, then just contact the department and ask to speak with the director of admissions or something to explain your case. And when writing your statement of purpose, you may want to explain the career change decision and how your engineering skills are transferable to Anthropology. Good luck.