...I've discovered that I have some wiring issues. One of which being no dashboard ground. I have no headlights. Some dash lights. Two tail lights! That flash! If your turning right...
Your problem with the two rear taillights flashing (with the right turn signal switch actuated) is almost certainly a short or damaged electrical connection within the turn signal switch in the steering column. If you click on the schematic wiring diagram below (twice), the diagram will be enlarged so that you can zoom in on the turn signal wiring. The turn signal flasher in the diagram is located near the top center, to the left of the cigarette lighter. The flasher is the only source of ON/OFF flashing voltage (via the 18 PPL wire) that is connected to the turn signal switch multi connector on the steering column. The brighter filaments in the 1157 bulbs in the rear of the car serve as both the brake lights and as the turn signal lights. These are filaments are normally wired to the stop lamp switch at the brake pedal (connected via the 20 B/W wire to the turn signal switch). When he stepped on the brake pedal, power passes through the turn signal switch to both rear taillights. Actuating the right or left turn signal temporarily disconnects the 1157 filament on the selected side from the brake light switch power source, and connected to an alternate power source (the turn signal flasher). This allows flashing power to be directed to the selected side only, while the other brake light remains connected to the brake light switch. This permits the two rear lights to both functions simultaneously — one with the continuous brake light and the other with a flashing turn signal. The fact that both of your rear lights are flashing at the same time (without an emergency flasher in the circuit) would only be possible if an internal short is occurring within the turn signal switch that is allowing flasher voltage to be applied simultaneously to both rear lights.
You did not say whether or not the two front signals function properly when the right or left turn signal is actuated. You also did not say whether or not the left turn signal functions as expected, or if the two brake lights function normally with the turn signal switch in the OFF position. Knowing whether or not the other brake light and turn signal light functions are behaving normally or have been disrupted in some way might help to indicate what is going on inside the turn signal switch. Unplugging the multi connector on the steering column and using an ohm meter to check for continuity between the various wire connections, while comparing the wiring in the schematic to determine the color codes that should have continuity with the turn signal switch in the LEFT, RIGHT, and OFF positions might help you to confirm how the incorrect switching is occurring. But ultimately I suspect you will have to pull the steering wheel and remove the turn signal switch to examine it to see if it can be repaired or if it must be replaced.
LEFT-CLICK EACH IMAGE TO ENLARGE FOR BETTER VIEWING
In looking at the contacts inside the turn signal switch, LR and RR are normally shorted together and in constant contact with B+. B+ only has voltage applied when the brake pedal is being depressed. Moving the switch to activate the right turn signal would normally deflect the metal contact away from B+ and bring it into contact temporarily with the other metal strip that is looped to TS+. The other metal strip is simultaneously pushed over into contact with the RF terminal, so that both the right front and right rear terminals come into contact with the continuous switching voltage available at TS+. This leaves both right turn signals flashing continuously until the switch position has been canceled. The left rear lamp would remain in contact with B+ and would be illuminated whenever the brake pedal is depressed.
In order for both of the bright filaments and 1157 bulbs in the rear to be powered by the flasher simultaneously, they would have to be electrical short somewhere within the switch or possibly in the wiring harness that allows the constant flashing voltage that is applied when the right turn signal is actuated to be carried over to the other 1157 bulb. This electrical short could possibly be somewhere else in the wiring harness or in one of the multi connectors. Such a short would not normally be noticed when the two bulbs are in the brake mode, since both lights are normally illuminated simultaneously when the brake pedal is depressed. However, if the short was in the wiring harness and still existed when the left turn signal was activated, you would think that both bulbs would flash in unison again when the flasher voltage was applied from the other side. If that is not the case, you will have to determine why the two are shorted together only when the right turn signal is activated, but not when the left turn signal is activated. Since the only physical movement takes place within the turn signal switch, the source of the electrical short may also be physically within the turn signal switch.
The headlights (high beam, low beam or both) are often disrupted by a loose connection or faulty switch on the floor of the car. This switch allows foot control of both high beams and low beams. Using a multimeter, you can check at the electrical connector to see if voltage is being applied to the floor switch when the main light switch is turned ON. If voltage is present with the switch ON on at the 14 B/LBL wire at the dimmer switch, and if the electrical connector is in good condition and firmly connected, but nothing is coming out to either of the wires connected to the high beam or low beam circuits, the dimmer switch is probably faulty. If no voltage is found coming from the main light switch, the switch itself may be faulty. A little troubleshooting with a multimeter should help you to identify the source of your problem with the headlights. Both switches can be found on page 84B of the Clark's Corvair Parts online catalog.
http://www.corvair.com/user-cgi/catalog ... N&page=84B
The instrument panel ground connections for the Corsa and Monza instrument panels are shown in the illustrations below. Both instrument panels are made of plastic and use a series of metal strips that are daisychained together to tie to a single ground point that is attached by one screw to the dashboard metal frame. A loose or corroded screw can create a faulty ground that can affect the operation of many of the lights and instruments throughout the instrument panel. You should check the physical connection of this ground screw and repair it as needed.