I have a set of 12,000 lb. rated Rhino ramps that are slightly damaged. I have a modified stone driveway (gravel mixed with a little bit of dirt for better compaction). My theory is that one of the larger stones must have been forced up against one of the plastic divider pieces under the bottom of one of the ramps. Anyhow, one of these divider pieces in the grid-shaped bottom is cracked about three-quarters of the way through. My first question is, could I replace just one ramp, or must I buy a new set? I guess I should call Blitz Mfg. who I believe are the manufacturers. I am concerned that even if I replace the ramps, I will run into the same problem. Would it be better to use two pieces of plywood on the ground before setting the ramps in place? Is there some potential problem with this solution? Would it be better to replace the ramps with a jack and jackstand set-up instead, or would these be worse off on a (fairly well compacted) gravel driveway. Lastly, how much does asphalt cost?