My symptoms for the starter motor (not the switch) were similar to Rarly's with the exception of the solenoid clicking. Mine did not click. The fact is there were two white SCs at the Glen with the exact same problem, I used the same little piece of red wire as the special tool to trouble shoot theirs as well as mine. Their solenoid did not click either. Both cars resorted to a more attractive female auxilliary starter motor.
FWIW -- I started with the Rarly approach to the top 10mm allen, but evolved to the Warren approach.
Alan
83SC