I got them home and into buckets (metal containers courtesy of my husband who got me about 10 from an abandoned Taco Bell) and covered them in a few handfuls of dirt from my backyard. The skull looks mostly clean in that photo, but the whole fleshy nose and mouth were still there, so I figured a few days buried with some dermestid beetles would help.
I ended up leaving it in the dirt for about a week total before I got it out and used a knife and steel wool to get the last dried fleshy bits off.
After a degrease and a wash, I realized that this little lady had some kind of nose deformity. The front of her face was curved to one side, both on the skull and jaw. Pretty cool! After this, I put the skull and jaws into a 50/50 water/peroxide bath and let them sit for about 24 hours (not quite, I'm impatient).