Board Racks

So my buddy has an 18' Chapparell (sp?) and doesnt want to spend the money on the tower right now but would like to create some more room in the boat. I was thinking he could get some board rack and fab up a hanger that mounts off of the side of the windsheild, with foam to cushion around the metal brackets and some sort of suction cup system to hold it steady. I was curious if anyone has ever seen anything like this or if the windshield could take the stress. I thought that it was a pretty decent idea but not sure of the reprecussions of it.