@Behappy - I believe the red, white and blue wires are for the remote receiver for the Hunter. Those don’t need to be moved over to the Rachio. Same goes with the black power wires - do not move them to the Rachio.
Edit: I didn’t have time to finish the original post. Yes, many times the common wire will be white, but I recognize the red, white and blue wires as the colors that Hunter uses for their remote control receiver. I would need to see where the black and purple wires go on the fourth Hunter SRC terminal (RS) to make a proper statement on if and where they should go on the Rachio. One of these wires will be to the rain sensor and the other will be the true common wire that will go on the Rachio C terminal.