Rear door jammed shut.

Hi folks

Have recently resurrected our 97 4-cyl 4runner after about 5 years of non-use.

Rear door worked fine for a while then stopped working.

The lock fitting had fallen into the mechanism compartment some time ago - but the door still worked.
I think that the lock may have shifted and now be blocking the opening mechanism. The pull handle works fine - and springs back correctly.
I have read that the plastic cover that I need to remove is held by one screw and plastic clips. ( on a later model, mind)

Trouble is I can't find the screw anywhere. Can someone tell me where it is ? It doesn't appear to be behind the tag plate.

Thanks
Steve