Found the problem(s)... here is the list of things I found that created the no-start problem:

1. Spark plug electrodes in the #3 cylinder. Someone just put another spark plug in rather than finding out why the electrodes were being broken off in the #3 cylinder
2. Carburetor needed replaced. Too many leaks.
3. Fuel lines plugged... varnish!
4. Fuel tank plugged... varnish!
5. And finally... conversion from 6V to 12V... much more power to the starter.