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LED Headlight Install with optional Headlight Adjuster Replacement

11 January 2021
Ontario, Canada
LED Headlight Install +/- New Headlight Adjusters
Boslla Bullet B1 LED bulbs are great! www.boslla.com

When I installed my LED's, I read every thread I could find. After doing it, I made these instructions with pictures

Google doc Instructions:

I haven't had much luck uploading pictures so I put it in the form of a shared google doc link. I also detailed optional instructions on replacing the headlight adjusters, which are often seized if they're original pre-1997. Hope it helps someone do it more efficiently than I did as something like this would have saved me ++ time.

PM me if you see a gaff so I can fix it. Also, please post your results here, preferably with pics.

On Bossla:

Related Prime forums on the cap design:

Related Dust Cap Thingiverse link:
Boslla Bullet B1 fits in a 53 mm cap
Boslla B4 series 3 color fits in a 75 mm cap

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Just made an important addition. Be sure the retractor covers are positioned to not rub on the hood. With the attaching screws, the covers can be adjusted up and down as well as fore and aft. On mine, the covers seem to settle a bit too high, looking fine when down, but rubbing the hood when moving, which could eventually damage the paint. Moved them down about 1.5 mm and they're perfect now.
With the caps, I inset a Honda H logo 0.2 mm to help align the caps when installing. If you print layers 2-4 in a contrasting color, not only are they easier to insert, you see the Honda H if you look "back" into the headlight housings (only when the hood is up.) OK, I'm a 3D printing nerd...
WhatsApp Image 2022-09-27 at 9.22.50 PM.jpeg
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On my 91 JDM after removing the bulbs I see a bulb retainer that looks very fixed as per photo - Am I missing something here or is this removable to follow the instructions1000064984.jpg
Can't see your location in your profile, but that definitely looks different than mine. Did you originally have 9005 & 9006 incandescent bulbs in there? The connectors also don't look like they would go on 9005 or 9006 bulbs - they look like 1/4" female spades? Do you have a picture of the bulb(s) that came out of there?

Looking at the third diagram here:
The diagram shows the female spade lugs on the wiring harness like yours. The incandescent bulbs seem to be H1.
Interestingly, both low and high beams are the same bulb; USDM has different 9006/9005 bulbs.

I presume you'll need the bulb spec for the JDM bulb to get compatible replacements. Something like this?

Hopefully, some other JDM owners can be more helpful than I. I think @Big McLargeHuge put LED's in his JDM?
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Looks like you're right - d'oh just assumed that the setup was identical between JDM and USDM for headlights. Have an extra set of 9005/9006 B1s now :) At least one of the bulbs is H1 as I read off the bulb just now - does look like both are H1.
I wasn't aware of of the difference either. ✅

I've updated the doc to specify 9006/9005 for USDM. Update us when the job's done with your JDM, especially if there are any other modifications for JDM install that you can provide pictures for.

LED's are a huge improvement - can't imagine you having any difficulties unloading those 9005 & 9006 bulbs, but Boslla also has an excellent return policy if you want to go that route.
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Sorry for coming in too late, but yes the JDM headlight bulbs are H1 style, not 9006... I did the same thing when I first ordered my LED replacement bulbs. I haven't replaced the high beams yet.

I could also probably adjust the headlight beams higher but hadn't gotten around to it :). The US doesn't care but I know in other countries (UK) you have to replace the headlight housings with the correct handed versions since a RHD car on a LHD road will throw more light into oncoming traffic than your own lane. The NSX is so low anyways that any modern OEM Honda/Acura or Tesla headlights will blind way more people.

The ones I used on my car are Hikari brand, they do a great job but using these types of cheaper bulbs in the past I usually had to replace them every 1-2 years on my daily driver. The NSX uses its headlights much less so I would expect them to last a few years longer. If you really wanted to ball out you could try the Morimoto 2Stroke bulbs (https://www.morimotohid.com/morimoto-2-stroke-2stroke-h1-led-bulbs_3?quantity=1), I haven't used them personally but the next time I need a replacement they would be first on the list.

Thanks TT for the dust cap files, with my new 3D printer I might use them make my high beam caps :).