Rejuvenate plastic?

Took the cover off my A/C and cleaned the condenser coil but the evap coil is incased in a plastic shroud that has 4 screws and 4 big plastic tabs. When I go to pull the tabs back to release them, they want to just crumble due to being exposed to UV for all these years. ( this is a Carrier Air unit) just wondering if there is any way to make the plastic a bit more stable