HEY!
That K3 has K2 gauges! It must be a real early K3!
Out of curiosity: look at the starter solenoid, see if it has 4 terminals on its top.
Also, look to see if there is the remains of a sidestand switch mount and/or a pair of wires hanging near the sidestand. This was parallelled to the clutch-lever START switch. They were all recalled and this switch removed, at one point in winter, 1973.
A precious few of these early K3 bikes had these 2 items, where the 4-pole starter solenoid turned off the headlight instead of the later SPDT Start button (it had a grounding button, like the K2). The 2 extra terminals interrupt power to the 7 amp fuse on the fuseblock, if they are there.
If so, it is a rare one, indeed!