Like bare says, no rewiring is required on the new UCE powered motorcycles.
Unlike most cars that have a single 3 slot plug that connects to the 3 prongs on the bulb, the Royal Enfield has three separate wires.
It is therefore possible to hook them up wrong to the new bulb.
When you make the change, take a digital photo of the existing bulb and wires while they are still connected. That will give you a good visual reference so you will know how to attach the three wires to the new headlight.
If you don't have a digital camera draw a circle with a short horizontal line right below the 12:00 o'clock position, a short vertical line at the 3:00 o'clock position and another short vertical line at the 9:00 o'clock position.
The 12:00 o'clock position represents the TOP of the light bulb when it is installed.
If you are drawing this 'go by' picture, write the color of the 3 existing wires that are connected to your old bulb.
I think you will find that the wire at the horizontal 12 o'clock position is tan or light brown. This is the LOW beam wire.
The wire at the 3 o'clock position will be light green. This is the HIGH beam wire.
The wire at the 9 o'clock position will be black. This is the ground or "common" wire.
If I have the colors wrong, use whatever color your wires have.
You may find a gray wire in the casquette. This is the "parking light" power supply.
My headlight doesn't use this gray wire but some headlights might use it for the small bulb that plugs into the headlight reflector.
If this gray wire is not connected to the bulb, it's a good idea to cover the end of the connector with a piece of black plastic electrical tape. This wire has power supplied to it whenever the parking or head light is turned on.