I finally pulled out the old platic windows and took them to the glass shop. The tech there convinced me that I should go with cast glass similiar to what they use in car windows. He made four new pieces and was able to remove the rub strip from the olds ones and install it on the new windows. Once back at the boat the windows slipped in easily. They look great and seem to slide smoothly as well.
Hotter than all get out in the midwest and south. Have not had the boat in the water since the M&C show in early June. Got to head to the lake soon.