That gap is much smaller. I now only have a 2x4 between the header rack and TC rubber bumper.
On side note to storage: All of the places I have contacted to build out TC side walls to enclose the wings have flaked on me. It must be their prime season and they are not hungry enough for my business. I have twice attempted to order storage boxes under the wings only to to have the companies come back and tell me that their supply count was off and they could not fill it - I really think their price was off (which is why chose them) and they didn't want to honor their goof. I'm looking at about $300/ea for four 48x18x18 utility boxes in steel or aluminum or can get poly-plastic boxes close to $200/ea in that size. There are a couple of 8' utility boxes available, but shipping is high due to the length and bulk.