Chevrolet VENTURE 1998 Manual page 193

Use the adjustable tie-down
loops in the side rails to
help secure large loads.
Reposition the tie-downs by turning them to the left,
then slide them along the side rail. Turn the tie-downs to
the right to tighten them in place.
Bumper strips on the luggage carrier crossrails help to
ensure a quieter ride.
If you wish to attach the luggage tie-downs or other
compatible bicycle or ski accessory racks to the
crossrail, use the adjustable tapped plates under the
bumper strips.
Lift the end of the bumper strip with
a
flathead screw
driver and cut off enough of the strip to access the
tapped plates.