You don't need many screws. I used 6 on the pipe originally which is way too many. On the second set-up I used 3 and it's holding fine. 2 screws is all you need, each, on the pipe and header, about 180 degrees apart.
Matt,
Yep, I ended up using only 3 on mine, only because I was too lazy to hassle with removing the header.
Holding up fine!