can't open door

[ZZracing@aol.com]

On an '87 5K, one of the rear doors won't open.  Central locking seems OK
(know goes up and down with key use).  Outer door handle "trigger" doesn't
seem to move.  Inner door handle moves through full range, but door does not
open.  I've looked through the Haynes manual to no avail - can't get to the
opening mechanish unless I can get the inner door panel off, and I can't
figure out how to do that without having the door open to access the inner
door panel mounting hardware.
Any help and advice would be appreciated.  Thanks.

David Zube, Vestal, New York
1991 90Q20V
1987 5000S