I would say it is not needed. Some that I know back the tires onto a small piece of plywood just to keep the tires from contacting the concrete. With stone, that may not be needed.
2011 351RLTS Eagle, Mor/Ryde suspension & pin box
06 F350 Lariat PSD, SRW, LB, CC, EGR delete kit, 16K DrawTite hitch, Timbrens, TST TPMS
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