That lightbar stup is made to be an add on to a "rollbar" (bed mounted lightbar) or a tube front bumber, not mounted to the roof. I personally wouldn't mount those on a roll bar for height reasons. the best place to mount that would be the front bumper. As far as bolting to the roof I don't recommend it at all. Waterproofing is the easy part, you just need silicon. But to me that doesn't look all that lite and ur roof is made of the thinnest, weakest metal on your truck. The weight of that setup combined with the bouncing on rough roads and whatnot is gonna trash your roof. The reason they make the light bars that attach to the drip rails is because your roof is not designed to support any kind or weight. Not tryin to piss in your kool-aid, just hate to see ya mess up your rig.