I doubt it. If you had it on the S terminal along with the purple wire, it would start cranking the engine when you turned on the key, or burn up that resistor wire. If you had it on the battery terminal on the solenoid, it would be hot all the time and engine wouldn't turn off. If you had it on the starter terminal, it would act just like it was on the correct R terminal.

I'm beginning to think nothing is wrong with your car. Bump the engine and check the voltage on the coil. Like Roger suggested, I bet the points were closed, giving you the 6.5 voltage reading. If it's still giving you the 6.5 voltage reading, check that wire at the firewall, if it's 6.5 there, disconnect the + wires from the coil and test. Maybe coil is going bad? Are you burning points?

 

Just for fun I took some readings on a car today.
12.5 volts at pos post on alternator

12.5 volts at pos on coil with key on points open (factory resistor wire)
6.2 volts at pos on coil with key on points closed(factory resistor wire)

Then I removed the wires on the pos at the coil and took a jumper wire from the pos post of the alt and ran it to the pos on the coil (bypassing the factory resistor wire)and took more readings.
12.5 volts at pos on coil with points open
11.9 volts at pos on coil with points closed

Then I got real inventive and set up a battery and coil on the bench.
I have a NOS ignition harness so I got it out.
I measured the factory resistor wire at 1.5 ohms resistance
I hooked one end of the resistor wire up to the pos on the battery and the other end up to the pos on the coil
Voltage across battery terminals 12.4v
Voltage between pos of coil to neg term of battery 12.4v
Then I ran a wire from the neg term of battery to the neg term of coil (points closed )and the voltage reading at the pos coil went to 6.4v
I then removed the factory resistor wire and ran a jumper to the pos and the pos coil read 12.4v
Pretty much identical to what happened in the car.
The coil above was a new No Name coil that said on it "use with external resistor".
I had on the shelf a NAPA coil that also says "use with resistor" and I ran the same test as above and it was very close other than the grounded reading (points closed)was 7.1v

OK other than taking a performance verification test for the insurance company thats all I've gotten done today.

EDIT - Just thought of something. I'm going to set up my bench test again and put a plug wire in the coil and see if I can get shocked.

 

hahaha.. ummm.. anybody heard from Roger lately?

 

I'm still alive . I was hoping for a big spark , all I got was wimpy sparks.
Would the distance from the rotor to the cap make it wimpy ?

 

Ground that dizzy and give it whirl... mwahaha