i have the "rutas del Mercedario y montanas del sector" book about climbing Ramada and Mercedario in Argentina. like to know if the walk into the area via los Molles is working without mules and if there are any topi maps available. want to climb those mountains in December

Basecamp for Ramada and Mercedario South Face Route is Pirca de Polacos with access via Valle de Colorado. The turn off is before Los Molles. The walk in takes around two days and involves some serious river crossings. It can usually be done without mules but a rope might be usefull especially early in the season.
For the normal route of Mercedario you can drive as far as Laguna Blanca. It is just an easy walk to reach Guanaqitos or the higher camps.
Both Valleys are connected through Paso Ancho - it is steep and prone to rock fall.