Sorry, I have to go into Richard Cranium mode for a minute.
If you're planning to put HID bulbs in your truck, you
really need to get a front lens that doesn't have the light pattern etched into it.
Unfortunately, I have yet to see a setup like that for the brick-nose headlights, although it may be possible to fabricate something from a piece of clear plastic or plexiglass.
There are two significant problems here:
1) The HID projector assembly already has the intended light pattern output built into it. Every vehicle with HID lights has a clear outer lens for exactly this reason. Going through a second lens with a light output pattern is going to throw the light every which way.
2) Even if the first issue wasn't there, the light pattern etched into the lens on these trucks was designed for a halogen bulb. The light coming out of a HID bulb does so in a different "raw" pattern than a halogen bulb, so the light pattern will be thrown off kilter all that much more.
As someone who drives professionally and spends a lot of time on the road at night, being blinded by someone who threw HID lights into halogen housings is one of my biggest pet peeves. Furthermore, it ends up throwing a lot of light in the wrong places (down immediately in front of you, which makes it look like it's doing well, as well as in the right spot to blind oncoming traffic) without really putting light where you really need it.
I'd be surprised if you haven't seen this link before, but I'll post it anyways:
http://www.danielsternlighting.com/tech/bulbs/Hid/conversions/conversions.html
I disagree with the article about no HID conversion being possible; it can be done properly if you get a full HID projector assembly (sounds like you already have this
) and a headlight housing with a clear front lens (which AFAIK don't exist as a bolt-in for the bricknose trucks, although you can get them for OBS trucks)...but, that's really the only way it can be done.
If you're going to do HID's,
PLEASE do it right!!
[/rant]