Are they all on the same fuse?

The same fuse protects the hazard, brake lights, and the Key in ign buzzer. I see no connection with the parking lamps other than the turn signal switch....
If there is power on one side of the fuse, but not the other side, the only possible cause is a bad fuse. However, if the fuse is hot on both sides, but there is no power at the hazard flasher connector, then you are correct in assuming there is a break in the flow of electrons between the fuse and the connector. It's rare to see a bad fuse terminal connection, but it's possible.
I would jumper a hot lead to the orange wire going into the hazard flasher connector, and see if that makes everything work. I know...that seems like a n impossible task, since the flasher is IN the fuse box, but you can run a wire into the plug, and then push the flasher into the terminal. If so, then it would be time to pull the fuse box off of the firewall, and have a look at the back side of it for damage.
The fuse box is bolted to the firewall from the engine side. If you look under the brake master cylinder, you'll see where the main harness goes to the firewall. In the center of that block, there is a small, 5/16"(I think...it may be 3/8") bolt. Loosen the bolt, and pull the connector apart. The fusebox will now be loose on the inside of the car. Then you can look to see if anything has melted. The fusebox/firewall pass-thru does come apart in two pieces...
hth...

Looking more like a turn sig switch problem.
Did jumpering the hazard flasher get the flashers working or not?
I'll bet you've got a turn signal switch fried, OR the connection on the column is corroded. Might be worth unplugging it to have a look, and then you can test for power going IN and OUT from there...
That sux if it is the t-sig switch, but it's certainly starting to look like that is the problem...


one other thought/kweschun...
While you were under there jumping the flasher, did you happen to notice a nasty, burnt plastic smell at all? I'm still curious as to why there was/is no voltage at the flasher terminals in the fuse box...there's gotta be a problem with that somehow...
Adams' Apple2009-10-04 19:25:15

I sended ya the wiring diagrams fro '73 & '74.
Looks like the next step is finding out why there is no power being supplied to the circuits. I would start by checking the voltage going into the tsig switch first. If there is no power going in(for the circuits in question), then I'd have to seriously consider pulling the fuse box off of the firewall, and looking for massive corrosion, or meltdown....

btw...the headlights do not go thru the tsig switch, so it's got to be a separate issue with that, but it could still be a fusebox problem, or maybe even a fuse-link, as far as the headlights...
Adams' Apple2009-11-02 11:12:49