I have been asked several times to do some research on the "Ladies in Pants" thing. As we all know, there is a definate lack of many pictures, I can think of four off hand, Little Britches and Cattle Annie, Several of Martha Jane Canary and Charlie Parkhurst. The problem here is that folks paying to have a picture taken seldom do not dress up. 150 years from now among the photo's taken by professinal photographers you won't see many of a house wife wearing what she wore that day to clean the house.
If one goes back in time a bit to the diaries of those who crossed the overland trails you will find accounts of many ladies who disscarded the dresses that got singed around the campfire for their husbands extra pair of pants and shirt or bought them at the first store.
To think that ranch and homestead women did any less is in my opinion to do a great disservece to these ladies. On the other side of the coin, many of us remember a Grandmother who worked around the farm in pants and shirts, but "ALWAYS" changed into a dress when visiting neighbors or going to town. These were women who grew up at the end of the era we portray so this needs to be taken into account also.
I often use the "Blizzard of 1888" as an example, "it's daylight, the storm has stopped in the night, your husband left before daylight to see if the children are OK since they didn't come home yesterday from school. You have a cow to milk, the chicken coop is covered and the drifts are 8 feet high between them and the soddy, wear you prairie dress if you want, but I doubt it."
This is the results of 5 years research, I can't say yes, but I won't say no they never. I do know the modern "show my butt" pants did not exist. But I would bet there were more women wearing pants than many believe, just not in the general public.
Since though the shooting done does not repersent the gay social shooting events of the time period, but are attempted to somewhat duplicate events that happened or could have happened, I would guess many ladies if push came to shove would not bother to change from "men's" clothing before defendin their home.