2005 Prius question about headlights

Thank you for taking a moment to read this...I hope I have this in the right section (electronics) ?
So I am facing a real nightmare...
My passenger headlight went out ...no problem (I thought) I will just buy a new bulb.
Imagine my shock when the price tag came to 189.00 ..for..a..bulb !
Yep...this car came from the factory ....with HID headlights.

I gritted my teeth and paid for the bulb.

Installed it....(actually it was minimal trouble)

and............nothing..still didn't work.
Turns out to be the ballast ...an additional 120.00 .
No no no no no....No way am I keeping this HID system in my car.

So....instead, I buy two halogen OEM headlight assemblies.
Cheaper than what the ballast would have cost.

Here's the problem....

The wiring...
The halogen bulbs do not fit the bulb sockets coming from the vehicle...
The sockets do not have a ground wire ..

There is no place where the sockets have been spliced in....it looks like the original owner opted for the HID upgrade at the time of purchase...

Guys....I cannot ....cannot...have these HIDs in this vehicle...so...is there any way to get the halogens to work..?
Some adapter I can buy....installing a ground wire isn't a big deal......but the sockets will not fir the halogen bulbs.
Really needing some help with this as I am currently down to one headlight..and on my way to work in the mornings...the cops are giving me the stink eye.

The wire that currently leads to the HID headlight assembly is...long and flat and has only two wires leading into it....white and a grey.
No black wire at all.


The halogen bulbs look like this: I I
_


and the HID plug looks like this I I
I I (The bottom two connections do not go to anything, no wires lead there)