Two of our blocks we use to mount the plexi came off...we've had amazing storms the past few days (though I love them, the materials we use don't) which seem to have damaged the bond. Our plan is to replace the wood blocks with plexi soon, but until then, we have to get a secure bracket system in order. We still have 4 that work, but we're going to use some PC-11, which holds even underwater, and see if that does a better job. Lisa examines the instructions here...