Yes, it's sealed. A little heat, not too much (don't wanna melt it) and a very sharp razor blade. Work your way around the edge where the plastic housing meets and you'll find a spot where it will slide right in. Once you find that spot, the rest should come off very easily. Use a clamp and clear weather-proof RTV sealant to reseal it. You can get auto-marine sealant at Lowes that will do the job. You don't need a lot of it, just enough to seal the tail light back to the housing.
Be careful taking off the cover, it is possible to crack it. The sealant that they use is extremely strong. If you feel a lot of resistance, find another spot.
Last edited by Zell; 01-28-2013 at 06:01 PM.