The taillight's out. Here's the gap:
And here's the offending taillight. Note the water that has spilled out of it. There was probably half a litre of rainwater in there.
Now let's look in the boot. The little tub is normally affixed to the right-hand boot lining. I popped it out to clean it. Note the objects it contained:
Note the boot lining behind the rear seat. Only one fastener is holding it in place. A number of trim fasteners seem to be missing on the car. Obviously, some have simply fallen off, as they tend to do. However, this looks like the sort of casual incompetence common among dodgy second-rate mechanics, do-it-yourselfers who really shouldn't, and questionable car audio fitters.
Here's the BMW toolkit in the bootlid. As usual, some goodies are missing, like the warning triangle, a spanner, a screwdriver, a towing eye, and some other bits and pieces that I can't identify. Look, if you take a tool out, put it back when you're done. If you can't do that, please kill yourself, because you're wasting the oxygen of people more valuable than you.
E34 toolkits come up regularly on eBay, so maybe I'll get one once I've fixed everything else. Or maybe I won't. Like most manufacturer's toolkits, they're more about ornamentation than quality, though some of the specialty bits -- like the driver to close the sunroof if the motor fails -- would be useful.
The best manufacturer's toolkit I ever had was the one that came with a 1987 Honda Gold Wing I used to own. The socket set was amazingly respectable. The rest of the tools, however, were the usual junk. We're not talking SnapOn(TM) here.
The new taillight is in place. Looking better already!
More next time...