You can take and place the side of the cross member of the trap frame on a hard surface and strike the opposite side of the frame with a hammer..this will compress the notch in the frame where the pans hinges.....just be carefull and check the play as you go....sometimes more is not better!
the ones i am working on have a solid post with the pan being the one with the split in it. I took the dremel tool and cut 1/8 inch off and squeezed it back on but it still flopped. I may do the pit pan add on. But if there is a easier fix and cheaper i am all ears! I hate to retire alot of my old long springs. They hold a special spot in my heart!