Just installed new brake switch, and still nothing.... I then happen to be holding
cable from PTO switch when I realized entire electrical system was
powering on and off when I moved cable.
Long story short... one or more of the connectors in the plastic plug was
out too far from plug. This was causing a poor connection.
Used a small screw driver to push connector in and starter motor now engages when key is turned.
So the PTO switch, among others, will actually prevent the
engine from starting !