So I went ahead and installed a 1/2" thick isosceles trapezoid shelf, fabricated from white King StarBoard HDPE Marine Building Material, in the anchor locker yesterday. I left a space forward to insert a wet vac hose to remove standing rainwater below the drains on both side of the boat the end of the rainy season. It is supported by the partition baffle in the center and for 1"x1" legs. The locker slopes 5/8" per foot and which has been sufficient to keep the aft anchor locker section against the bulkhead dry. I guess the fiberglass lay-up guy did a good job that day. Now the rode is off the locker bottom and dry.