I picked up a momentary push button type switch today and wired it up. Although i am just using a jumper to connect to ground right now, the switch works. So now, I turn the key to ON, nothing happens, then, at MY convenience, I push the button on the new switch, and to my delight, the starter engages. Also, much to my chagrin, when I release the button, the starter stops. Now all that remains is finding a permanent ground to wire into the new switch, and a permanent mount for the switch itself.
Many thanks to everyone who gave me advice on this issue. It's nice to have you all to bounce ideas off of and learn from. (turns out this IS a negative starting circuit!)
On a different note, for the first time I tried to see if the bike will run. I sprayed some carb cleaner in the carbs and hit the starter and to my amazement the bike sputtered and barked to life. Another shot of spray and a few cranks of the starter later I had more sputtering. Though a far cry from running, idling, and using normal gas, I took this as good news and a morale boost. I will keep you all posted with my updates and issues as they arise.