Did you cut your old hangers off flush with the chassis? You can see how it has a curve on the ends of the hanger. I plan to cut mine soon...and them curves are getting cut out...so that my drop hanger sits more flush with the chassis with very little gap between the cross member and my drop hanger. If need be I will add some flat stock between the two if I feel I can't weld the two together along the front and rear of it. Guess, you can say the flat stock would be a filler for the two to get welded up. That may be what you have to do.
But, I say post up a pic to see what you are working with.
Mike