Door drop down

I have a 1964 convertible impala ss,
just had frame off restoration, the
problem we are having is when the
doors open they seem to drop down
to where when you close them you
have to left up to close and to get
into the right perspective slam the
door shut, new hinges and striker
plate assembly, it looks like the when
body part they are attached to
causes the vertical part of the
windshield to dip, what can i do to
correct the problem