Rear Light
Moisture is a major problem for these tail lights. I tried like hell to stop the moisture from getting into mine by using plumber's putty and other stuff. Finally I ended up replacing them with the 98-02 style lights (I have a 95). 1st thing I would check is your reverse light fixture. Your leak might be right there and if you replace the rubber gasket (pennies on the dollar), that would fix you right up.
To check this out, pop the hatch and remove the plastic behing the tail lights. Take out the reverse light by turning counterclockwise 1/4 turn and pull straight out. See if the rubber gasket is damaged or missing. If everything looks OK, turn the gasket around and put it back together. If your leak is being caused by the epoxy joint that holds the cover on, you may need to replace the tail lights all together. Factory ones are expensive (>$500 for a pair). I found mine on ebay for $190 (for a pair). You could also check out junk yards.
The water was so high in my tail lights, I could have had a live aquarium in there (NO JOKE!!)

