Clutch engaged = loss of power???

[1983 Rabbit LS 1.7L]
So, I have this weird issue…

When releasing my clutch pedal, I lose power. One of the relays clicks as soon as the clutch is let out fully (presumably fuel pump relay), red battery & oil LEDs light up, dash lights/radio/dome light go out, fuel gauge drops to E, power steering is lost, etc. This occurs when the car is in gear OR in neutral, parked or moving.

Just like a regular stall-out, I have a few seconds before total power loss in which I can quickly depress the clutch and keep it running. During this period, I can hear my fuel frequency valve is still buzzing (but this is after the relay clicks, so maybe it's not the fuel pump relay?).

The car functions and drives normally if I ride the clutch (let it out allllmost all the way). Sometimes, if I let it out incredibly slowly, I can remove my foot from the pedal and the car will be fine for a few minutes, but this does not last long… and it might just be because it gets stuck in place from being released so slowly.

This started happening in the middle of my drive this morning, and I rode the clutch the rest of the way to work (*cringe*). When I parked it, put it in neutral, and released the clutch, I removed the key from the ignition and the door buzzer went off (door was closed). I opened the door and the buzzer shut off. Clearly this is some dastardly electrical gremlin, but I have no idea how to puzzle it out. I assume that I have a bad ground somewhere and part of the clutch pedal apparatus is grounding that open circuit when the pedal is released all the way? The car was running great last night and this morning (until I got to a stop light and it died when I was getting into 1st gear), so I can't think of any cause.

The clutch cable itself doesn't seem to be making contact to anything it shouldn't, and the wiring harness is tucked away and nothing is touching the pedal apparatus that I can see. I guess if something is improperly grounded there wouldn't need to be wire-to-clutch contact. Clearly I'm not an electrician Something that could potentially be related is that I have had issues with getting it into reverse and the reverse lights are finicky. The lights turn on for a second as I start backing up, then shut off. I haven't analyzed this in depth, but it wouldn't surprise me if the lights are only on as long as the clutch pedal is fully depressed.

Any ideas? Ground points to check? Anything!  

Replace the Battery to Frame, and the Frame to the engine ground. You can get them at any parts store one battery to frame then battery to battery jumper strap for the engine.

Sounds like you are using your clutch cable for main engine earth, and when you engage a starter you could fry your cable.