Wow, tough call. I tend to be longer torso but still run about 81 cm seat height (I'm 6'+ with about a 35" inseam). I would try and go with top tube first, that usually means a bigger frame, but maybe not in your case. I ride a 58 Cannondale (130 stem), 61 Bianchi (120 stem), 60 Trek (120 stem), seat to bar distance is within 1cm on all three. Check standover and go with the best fit for the top tube.

John