How to Get Window Trim Back In??

Does anyone have any hints on how to get the rear quarter window trim back on for a 911 SC? The window is out of the car. I can't seem to get the metal trim to fit back in the rubber seal. It simply will not "click" back in and grab hold.

Any hints would be appreciated.

Frustratingly yours,

Brian

Thanks for the reply. Where can I find the Helper springs. Should I replace these?