The factory rails you say..... my truck only had two plastic strips bolted to the roof. Are these the rails you're talking about? I just pulled them and put that foam tape on the feet and bolted it down. It didn't look like it would sit on those rails very nicely.
It did feel a bit low and it was suggested that a 3/8" spacer would be nice by my father as we installed it.
Also, you sent two different sets of screws, I used the 4 short ones to bolt the feet down. I'm going to get washers for them though since the heads on them aren't much bigger then holes they go through.
And yes, it is super slick where it is. It does touch the roof on the bottom of a few of the cross bars. It doesn't bother me though but someone might not be happy about that. You can see this in the video walk around. The front of the rack was really close to the roof too. I had to cut the rubber pieces to get them to fit between the rack and roof. I also had to loosen the screws in the front feet and then put the front mounts in. No bigger but if you cranked them down they would cause the roof to start to bow in under the feet.
I'm a little hung up on what lights to get now. The front light spots are fairly small. 13"W x 3.25"H x 3"D. So it's not a big space. I've been looking at 10" LED light bars since they'll fit in the rack but haven't decided yet. I'll start a new thread for that discussion.
Also, it does start to whistle at 65 but that was expected. It's not very loud and I had the windows down. I'm sure if I closed it up and turned up the radio I wouldn't have noticed. Also, it must have stiffened the roof a lot cause my aftermarket sunroof now rattles even more. Neither off these are complaints about the rack.
I cold surely go on. If any one has any questions feel free to ask. I'll get a picture if requested and I'll answer whatever I can.
Over all though this is an awesome rack that changes the look of the truck nicely. I should still fit in the garage too but i haven't tested that yet.