Ok, I have been thinking about getting a tonneau cover for my White '03 Silverado Ext. Cab Long Bed. Here is the problem. I have a compressed natural gas (CNG) tank in the bed right behind the cab with a cover on it that is raised about 2 - 3 inches above the sides of the bed. Is there a tonneau cover available that will fit over this tank cover? I have seen CNG Silverados with tonneau covers before, but the top to the tank cover has been cut off to make the tonneau cover fit. Here is a picture to show what the tank cover looks like. Thanks.