I tried an HID kit on my 660Z may years ago. The difference in light wasn't worth the hassle.

The HID would have a problem starting in the first place due to the engine cranking over at the same time causing a voltage drop exactly when the HID kit needs most of its power.

The second problem is that on the Z the main beam bulb and dipped beam bulb are not on at the same time. Fine when transitioning from dipped beam to full but if you had been running on the full beam for any lenght of time then switching back to dipped beam plunged you back into darkness while it, hopefully, started again.

I had to run seperate wiring for the HID kit from the battery through a switch on the bars so that could "re-boot" the light if it didn't start up first time which also meant that the kit was on all the time regardless of the high beam setting.

Eventually I ended up putting the lights back to standard and installed a separate set of LED spotlights to give more light when required.

Al.