screeching brake pads

my girlfriend has a 99 galant es and I just put brand new struts,rotors, and brake pads on for her. My problem is now when she accelerates, a loud screeching noise comes from the front passenger side. when she parked the car that same rotor was really hot. I'm almost positive it's that the brake pads are too tight and causing friction with the rotor. my question is how can I easily loosen the pads and/or calipers to the point where it doesn't cause that friction and its still safe to use? and without causing myself any extra work? can anybody correct me if it isn't what I'm thinking it is?

If the brake pads were installed properly, there should be no such thing as "too tight". Take it apart and look it over. Chances are something was done wrong.

may have a bad caliper or pinched or bad rubber brake line