My Ultimate 5th Wheel Hitch doesn't sit flat in the bed of my Ford. Is that a problem?

A lot of different trucks have obstructions in the bed of the truck and our hitch needs to sit on an even surface in order to properly function and spread the RV weight to the frame of the tow vehicle.  The best option for anyone who has 'pucks', safety chain loops or any other intrusions through the bed of the truck where the hitch sits should purchase an item like this and cut out around any items so the hitch fits completely on the pad:

http://www.tractorsupply.com/tsc/product/utility-rubber-mat-black-4-ft-x-3-ft?cm_vc=IOPDP1