Search the Agave forum for "Agave Mite". There is a thread with some more info. A. guadalajarana is one of the most susceptible species. I have been trying the new miticide spiromesifen (Forbid 4f) and having some very promising results so far for treating both Agave and Aloe Mite. If the plant isn't really special to you I would remove it from your property and burn the ground it grew on
. It is very "contagious" so to speak, and your other plants are at high risk.
Allen