Update: I fixed the light leaks for the most part, but since 95% of my shooting is done in cloudy/rainy weather, I figure it wasn't much of a test.
I recently did a lot of shooting in intense sunlight and found a good portion of my negs ruined by light leaks. This is just one of many photos afflicted, all of them with a leak of the same intensity and location.
I'm trying to figure out where to locate this particular leak so I can go in and add some more foam. The image is flipped upside-down, correct? So based on this the leak is coming from the center, spanning downwards on the left side of the back?