I know this is an older thread, but I have a 99 2 door Tahoe also that did not come with the factory roof rack. I found one in a salvage yard several states away and I was thinking of putting this on my tahoe. How big of deal is it to install these? I am just basically drilling a couple of minor holes in the roof above support beams? I have the head liner out already but I have never seen how the bolt on. Long term I want to add a cargo basket and I was also wondering if I need to beef up the mounting hardware to support the added weight of a cargo basket down the road? Thanks for the help!