I had to move the toolbox an inch and a half to the back of the truck to clear the lid when open. If your toolbox has a recessed hinge you may not have to move the toolbox back. The Weatherguard toolbox fits between the base angles of the rack with a quarter inch to spare. My toolbox is an older version that doesn't have the recessed hinge, I think the new ones are recessed but you should check. It took a bit of adjusting but I was able to get the Magnum rack, Access roll up cover and the toolbox to play nice together. Just the 1-1/2" gap in front of the toolbox.