If its ours, make sure the top parts is laid up right where you want it before tightening anything down. Also, the seal that goes around the sides can be tricky if its not tapped on all the way. Its made to sit pretty prefect so everything needs tapped on and lined up before tightening anything down. Mount it up to the catch before tightening....and it really helps to have a 2nd set of hands. Its hard to maneuver that big windshield by yourself.