brake lights, turn signals, and hazard lights

Hello. I have an 84 LeBaron convertible that I've owned for about three weeks. The brake lights, turn signals, and hazard don't work.

Here is the chronology:

1) Bought car, got it home, noticed that brake lights, turn signals, and hazard flasher didn't work.

2) Changed rear bulbs, changed fuses, though all looked fine. Changed flashers for hazard and turn signals.

3) Brake lights and turn signals worked fine, but hazard did not.

4) "Cleaned up" fusebox, replacing some incorrect fuses with correct ones. Stupidly trusted a website fuse chart and left fuses 15 and 16 empty, since they were marked "spot light" on fusebox and on chart.

5) Car wouldn't start. Starter was going but wouldn't turn over. Then I got no ignition/starter response at all from turning the key (all instrument lights, chimes, other electrical systems worked fine). Received the owner's manual I had ordered and discovered that 15 and 16 were turbo and coil. Felt stupid and fixed that.

6) Spent days trying to get car to start by replacing things. Codes told me hall effect sensor and auto idle motor (decided idle couldn't have anything to do with the starting problem I was experiencing). About four relays and sensors (starter relay, hall effect, etc) later, just before I got out the jack to take off the (new) starter, replacing the "fuel pump relay" made it start right up. Turns out that this part was really the auto shutdown relay or starter shutdown relay, NEITHER OF WHICH IS MENTIONED AT ALL IN THE HAYNES OR CHILTON MANUALS in my possession. One would think that a crucial component like that might figure in one of those books somewhere, like, um, troubleshooting, or the starting problem matrix, or chassis electrical, or somewhere.

7) Car starts and runs fine, but-- once again-- brake lights, turn signals, and flasher don't work. Fuses and bulbs are fine, and everything else on the circuits works.

8) Fiddled around with brake light switch, but it's impossible to get to in terms of having a sense if it's any good. Plus, why would they have worked earlier but not now when the car did not move at all between the brake lights working and not working?

9) Have a new brake light switch and will try to install it, but am not convinced that's the problem.

10) No idea what to do with turn signals, since everything else on the stalk (headlight dimmer, cruise control, wipers) works. Only thing I did not replace was cornering bulbs, but, again, the blinkers worked before without my replacing them.

Any suggestions welcomed, unless they are "find a short."

Seriously, unraveling dozens of wires from their routing tubes and tracing them to all ends of the car does not seem like a solution, unless there is a faster way of checking continuity I don't know of. I might as well install completely new redundant brake light, blinker, and hazard wiring if I'm going to do that. But then I am far from an expert on this at all and am very likely missing some assumed knowledge about the process.

Thank you for any ideas.