Ive had my stove for a couple of years and it's set back into the fireplace recess with a plate to stop the draughts. I bought an elbow so I can bring the stove into the room a bit to give me more heat but I can't get the back screws loose to get the back plate off. Is this because they have attached themselves due to the heat or am I doing something wrong. I'm a small female so perhaps just don't have the strength to turn the screws?? Please help. Thanks.