I just remembered I have a box of those Trucklite BO lights in storage - time to put one on the M1009
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As others have said, Halogen will keep the LEO from "probable cause" stops since they look stock for an 1980's truck. They are also cheap to replace. If you're looking for an improvement in light output, start with a headlight wiring harness to tap the batteries directly with a high current relay (a good start no matter what lighting solution you settle on). LED are available in full DOT compliance from Grote/Maxxima, Trucklite, and J.W. Speaker (in order of price, lowest to highest).
HID's are most often of questionable legality - anyone who sells you a retrofit bulb without a HID-specific housing calling it street-legal is putting the illegal equipment burden on you. Avoid! Avoid! I ran them "illegally" for years on a previous vehicle, but only after I took the fixtures and bulbs to a third-party lab to verify that the light output matched the SAE requirements for headlight beam patterns. They only didn't have the SAE HID markings on them which is what made them illegal (but I had that third party test report if I needed to go to court). I don't recommend this solution, unless your intent is to take off-the-shelf fixtures which were originally designed for HID bulbs and fit them into the 200mm rectangular headlight opening (can be done with Hella 90mm modules). That said, in years of running HIDs I have gathered enough experience with them to also say "stay away" they only increase the bulb life from 500 hours to 5000 hours - LED can get you an additional 10x life on HID over the 10x HID's would give you (so LED should in theory last 100x as long as a good Halogen bulb).
"White" is what is specified for headlights as a legal term, but I've yet to come across a jurisdiction which has defined a scientific color point for white, a 6500Kelvin headlight compared against a 3000Kelvin headlight will look like yellow and blue. The human eye is NOT a scientific instrument, it's only good at comparison - if you're handed a ticket without your headlight being placed under evaluation against a reference color or a colorimeter, there is a pretty easy way out of that ticket.
It's not just about lumens and color temperature, you also need to worry about CRI (Color Rendering Index), which has to do with how well colors can be perceived when lit by that light source. The sun is the reference standard and is equal to a CRI of 100. Typically the higher color temperature LED the lower the CRI, most high brightness LED fixtures with a 6500Kelvin white have a CRI under 75 (or you will only be able to perceive 75% of colors that you would if your environment was lit by the sun). LEDs with a 3000 or 2700Kelvin white more often have a CRI above 85, but they sacrifice lumens for CRI. Very expensive LEDs are available right now that have a CRI of 95 AND high lumen output, but they are often not used in aftermarket automotive forward lighting, they are used in showroom lighting that costs a lot of money... The
CRI for the LED which is used in Audi and BMW factory LED headlights is only 70. Tungsten halogen bulbs will give you a CRI of 95 or greater - most of this is in perception of reds.
If you're looking for a "cheap" improvement, try some AutoPal 200mm rectangle H4 housings with H4 bulbs and a headlight harness. If you want the "best" go with either a Trucklite LED headlight or J.W. Speaker LED headlight on a headlight harness.