It will fit on both sides. If the pressure is too high...

it will blow the safety valve and will not kill him.
But for a guy can not tell the difference between radiator and condensor... I would not suggest him to mess around with AC system.
If he is lucky, he can get it down right. But... what if... that will be alot of money for a coolant change.
Remember, this was start from changing coolant which I do not understand why he need to do that in a hot summer day.