Replaced the speedo, now all electric is out but the cigarette lighter! What'd I do?

[PanhandleShantyman]

Today I did two tasks and now while the battery is fully charged, the truck is dead-dead (absolutely nothing when I turn the ignition) and the only thing in the truck getting power is the cigarette lighter. Will a wiser head than mine tell me where I went wrong?

Task one was just to hook up the U-shaped connector to the new turn signal switch I put in yesterday. (The truck still ran fine yesterday after I finished installing that switch in the steering column.)

Task two was to take off the dash panel, put in a replacement speedometer, and put the dash panel back in. Getting the headlight pin out of the switch body did take a little wrassling around, it was a little stuck, but I didn't feel me breaking anything in that switch.

Anyway, I go to start the truck and absolutely nothing happens except the alternator indicator light came on appropriately. Engine doesn't turn over at all. Headlights, Horn, Dome light, Heater fan, wipers, turn signals , none of them work. The cigarette lighter has power, that's it.

The battery is fully charged and the fusible link looks fine.

What could I have done in the vicinity of the headlight switch that completely disabled the electric system? Or could hooking up my new turn signal switch have done if if I had something wired wrong? (I'm pretty sure it's all hooked up right though). is there a single fuse besides the fusible link that could blow and completely kill all this stuff? I'm about to break out the circuit tester, but if somebody wants to make a prediction of where my problem is I'd appreciate it!