Manufacturing defects abound! I started putting it together following the instructions, 3 screws on the cross supports will not go in due to the welded nuts not being aligned with the join brackets, i got the supports in place with  3 of the 4 screws on 3 of them assuming when i squared it all up with the roof supports that they might align or i could use some leverage. But when i got to the last 3 roof supports I could not put the 2 pieces together due to what looks like metal debris in side not allowing them to slide together. See photo.