Cadillac 2005 XLR Owner's Manual page 106

11. Reach behind the square hole and push the front
tonneau over-center link up. The front tonneau
should pull up easily. If it does not, push the
over-center link up more.
2-50
12. Manually move the front tonneau to the open
position. Once the front tonneau is open, fold
the side wings in by gently pressing them in. Do not
force the wings. If they are hard to move, make
sure the front tonneau is open all the way.