Price paid: around $30
Installation: easy
Negatives: none
Overall opinion: great
I purchased my trunk light kit from subaruparts.com. It did not come with instructions but it is easy to figure out. The kit includes the light and a new trunk latch with a switch connected to it. The wires for it are already in the car. The light pops into a hole near the tortion bars on the drivers side. The grey plastic cover around the trunk latch needs to be removed to install the new one [trunk latch]. It makes a loud snap when it's popped off (pull straight up), but I guess thats normal.
The most difficult thing is popping off the release cable and then putting it back. Plug everything in and you're all set. As usual, the car should have come with it already. This is a worthwhile mod.