you make the armor roll then subtract the base value from the incoming damage, and figure out if the shot pens or not!
10 damage hitting straight on, no armor roll needed because 10-10=0, roll outside damage;
14 damage hitting straight on, roll armor, if less than 04 armor passes, 14-10=4, the shot penned — roll inside damage.
btw sorry for the late reply, batshit month 😔😔😔 if i can help with anything else, feel free to ask!