I have bought a new deadbolt. Dexter by schlage, double keyed deadbolt JD60/JD62. I have put in bolt, put in outside cylinder with mechanism in horizontal position, put on inside cylinder with mechanism in vertical position and matched up the screw holes. But I cannot screw in the screws. It seemed so easy but after spending hours trying to screw the final screws in I'm getting frustrated! Anyone know what to do?