before i get too far down the rabbit trail i see they only have 4 1:100k scale maps-none for ares we're interested in- so have to use ensenada H11-2 1:250000 base scale map,and from there using autozoom to actual scale have to figure where the mine etc is on the large map so can select the proper 1:50000 scale map
http://mapserver.sgm.gob.mx/cartas_impresas/p...1-2_GF.pdf