Gap Between Frame and Bracket on Curt Gooseneck Hitch for 2007 Chevy Silverado 2500 Short Bed

We have installed this as per the enclosed instructions and the online videos.. torqued down to 40 ft lb as per instructions - there is a gap between the bottom ubolt and the bracket and the frame - looks almost like there should be a spacer ??? none were included. Just want to confirm that this gap should be there and is safe for towing? It is the same on both sides. The ball is centered where it should be and everything else is correct placement.

asked by: Stefanie