:welcome:
The white should go to the magneto , Verify this by checking it is open circuit to ground with the ignition on, brake on and pto off then gets continuity when the ignition is turned off.
It must never show any voltage.
On most simplicity mowers the purple goes to the fuel shut off solenoid and the orange goes to the alternator.
However the youngest Simplicity wiring diagram I have is 2005
If this is the case the Purple will be a light wire & the Orange will be a heavy wire