How do you change the brake light in a 2005 Subaru Outback no little doors like there used to be?

For the first time, I just had to replace the rear turn signal bulb on my 2005 Subaru Outback wagon. I ran into the same question as you. The access door that existed on earlier Subaru wagons was not helpful, as you say. Not close enough to the lamp assembly to help... I managed to download a good many pdf's of Subaru technical service manual stuff when I first bought the car. I looked up how to change the rear turn signal lamp. The documentation was a little confusing, but I managed -- after about 30 minutes of confusion -- to figure it out. There are two little black Phillips head screws that you can see in the little black panel piece between the rear door opening and the tail light assembly. I first tried removing those two screws as one would any Phillips screw: Insert Phillips, turn counterclockwise, and wait for the thing to turn its way out. This, however, did not seem to be doing anything -- the screw just turned as if it were stripped or something. I could tell from the documentation that those screws were somehow removable. The secret was this: Put a Phillips screwdriver into the screw, but put NO pressure on the screw to hold it in. If you merely turn the screwdriver counterclockwise (about 1/4 turn) WITHOUT pushing in on the screwdriver, you will see that it will turn itself out just a little. Once it starts coming out, just grab it with your fingers and pull it out. These "screws" are really just little expansion devices to keep that black panel piece in place. Anyway, remove those two screws/clips/whatever they are. At this point, you can wiggle that black piece a little, and it will come completely out. There are 3 little hidden hooks/clips holding the piece to the light assembly. The owner's manual says that you have to use a flat-head screwdriver to pry the black piece out of its clips. It tells you to cover the head of the screwdriver with tape (I guess so you won't inadvertently scratch the lens) and to put it between the light assembly and the black piece and use it to release the clips. I needed to do this, but it may be that you can release the clips merely by wiggling the piece.
The purpose of that little black piece is to cover up the REAL fasteners that hold the rear light assembly in place: two 10mm bolts. Remove those two bolts. Now comes the second piece of information that you need to know to keep from damaging your light assembly. Once you have removed those two 10mm bolts, you will notice that the light assembly stays somewhat firmly in place, as if something else had it attached to the car body. Really, there is no third bolt or anything; instead, it's like it pushes into a small track or something, and it must slide out by pulling on it exactly toward the REAR side of the car (as opposed to the SIDE of the car). In other words, stand directly BEHIND the light, grasp it, and pull it straight out the back, without bending it in any fashion toward the SIDE of the car. Turns out it comes out rather easily as long as you tug on it the right way. The rest of it is simple bulb replacement as in many other cars. Find the right bulb (7440 is the Sylvania number for the turn signal lamp, 7443 is the number for the stop/tail light lamp), and replace the bulb. The remainder is just the reverse of the disassembly. So, only two things a bit unusual: The little black Phillips "screws", and the direction to pull on the light assembly once the fasteners are removed. Good luck. BTW, my wagon has 47K miles on it and apparently needs a new hub (wheel) bearing. Do you know if anyone else out there is experiencing wheel bearing issues with the 2005 Outback models? Again, good luck.