Thanks for the quick reply. Interestingly, the light brick fully lights up when the lever system is pushed in a certain angle. But yeah, probably have to get this thing out. Also needed to do this with one of the front ones. There, the problem was the switch needed to go in all the way so that the contact to both batteries was made. Here, I bent the metal contact a bit so that the light goes on with minimal press of the switch. Probably have to do this for the rear one as well ๐. Really unfortunate as I checked everything multiple times during the build.
As for the doors, I included a close-up view. As already mentioned: The door pieces will simply not stay in place. Do they need to be slightly rotated?