Now that it's cool enough outside to need it again, I finally got around to this project. http://www.wakeworld.com/MB/Discus/messages/65921/688353.html
It was TOO EASY!
$12 piece of plexiglass from Home Depot. Bought felt bud didn't need it. Used cardboard template to test in place prior to cutting plexi. I made the width 1/4" larger than exact measurement so walk-thru cushion would hold it in place. Taped plexiglass before cutting. Filed rounded bevel edges on all sides of plexiglass. Edges were so smooth I did not need the felt (simple is better). Easily fits in rear locker on engine wall. Total project time: less than an hour.
Finished plexi dam