I am left handed right eye dominant and this is what I have done.
left arm extended then drift over to line up with my right eye (right hand supporting). I find that this work well at close ranges but at 25 yards I must close my right eye and make my left eye do the job. I suspect that the minor difference in angle as I drift my arm over to the right effects accuracey as distance increases.
Life is a web woven by necessity and chance...