When the clutch switch is engaged, it doesn't matter which position the seat switch is in. On this tractor, you can set the park brake and get of the seat if the pto is offline. It cranks, so the clutch switch should be working. One side of the clutch switch is normally open and the other is normally closed if you wish to verify. The normally things with the pto switch actuator on these seem to turn into a no crank problem. Sounds seat switch like to me.