I believe that the ski rack will fit with the hard box .... the 4 pair ski rack is 30 inches wide at the widest part, which is the bottom that mounts on the cross bars. Please be aware that you will need lifters and longer mounting bolts for your ski racks to carry either skis or snowboards stacked on top of each other in the rack. If where you purchased the racks did not give you the lifters, call Thule (the manufacturer of the ski racks for Hummer) and they will send them to you ... good luck.
Michael
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Pewter Hummer H2
Northern California
www.zootsuitstore.com
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