I built my cart/storage rack with the PVC rails. Seems to work perfectly, no deformation in the hull at all in my horribly hot garage here in west central Florida. I know it says that in the owners manual, but dang flipping my PA 14 over, SCREW THAT! I just built the height of my truck bed and it slides right in. Within 1 minute it's out of the garage and being strapped in. When I get home, slide it out wash it down, back in the garage.
I have a pic of mine on here as do others that have done similar things.
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