Smoked Lexan Sliders
I recall having the plastic sliders come out by lifting up. There should be enough of a gap in the upper & lower grooves that you can lift the plexiglass up and be able to clear the lower groove. If you can't get replacements from Catalina direct, then have copies made from a reputable plastics dealer (like TAP plastics). And remember that the height is important, so that you can install the same way. Good luck.