Hi, John. Thank you for the reply.
I thought that may be the case, as I was unable to find any references to a starter lockout in any documents, diagrams or info I have on the 68's...
Seems a bit odd not to have a lockout circuit of some kind though, but, of course, those were the good old days when cars weren't built to be idiot-proof !
An interesting automobile related trivia question would be: Which manufacturer, and when, was the starter lockout circuit introduced.
By the way, I had already jumpered the purple wires, after removing the harness from the shifter switch.
Thanks again, John, for your help on this and many other issues!