Question for those that have done Koito headlight upgrade

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So, in process of installing koito halogen headlamp kit. The new harness has headlamp plugs that will require me to hole saw the headlamp buckets to feed harness through to reach bulb.

Is that what everyone else has done or am I missing something?

This is on a 1970 40.

Appreciate any help from those that have done this mod!
 
Check out this thread same question

 
On my 1970, I shortened the wiring harness for a tidier fit. In doing that, you can either trim it to the proper length, feed the wires through from back side of the bucket through the hole and crimp on new locking spade terminals to put in the plugs. Or, you can cut a big chunk out of the middle, feed the headlight end through from bucket side and solder the wires back together (or some other connection form).
 
I posted about this year's ago on some thread from here. You could probably find it if you went through my profile's history (I can't remember if I included pictures about it) ..... I have a 1971 and has the same closed headlight buckets like yours. Take them apart and you should be left with the wiring harness with the headlight plug. You can seprate the individual wires out from the plugs. It takes a bit of time. I remember having to use a small flat head screwdriver an maybe another thin enough tool to push out the wires/spades from the plug. Once you do that you can feed them into the new koyito headlight harness plugs. After thats it's pretty much plug and play. I fed the new wiring harness underneathe the radiator support and grounded the wiring to a bolt near the drivers side fender inside the engine Compartment.
 
Thanks for the help guys. It is like I was thinking. Theres an easy way that works but isnt real art work when done. And theres the other route of making it fit nicely by taking the wiring harness apart.

Thanks again, was just making sure I hadn’t missed something blindingly obvious (I’m getting older and it happens).
 
On my ‘75, this was a non-issue but…once you get the install finished you’re going to love the improvement…good luck
 
that’s interesting. i have an early 72 and had no modifications to do. just plugged the new harness into the back of the new lights and wa la! i didn’t shorten my harness but uses some of the many zip ties that came with it to tuck it out of the way

do you have pictures of your light buckets?

what year did the buckets change? maybe someone upgraded mine but i thought early 72 shared a lot of stuff with 70+
 
I trimmed my harness like @Skreddy . Made feeding the wires through the buckets a breeze. :)
 
Anyone who cuts holes to feed the H4 plug shouldn't work on cars (sorry but it's true, it takes longer to hole saw). De-pin the plug and feed the wires and reconnect. Better yet, do that, mock up length, cut and re-crimp new flags for a quality installation that doesn't look like you went to O'reilly and crimped some wires together....

Yazaki/Sumitomo/Mitsubishi/Hero H4 Flags (to shorten and recrimp headlamp connector)
1726501441374.png


Yazaki/Sumitomo/Mitsubishi/Hero M8 ring terminals for 14-18awg....for the ground and power to battery.
1726501521906.png
 
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that’s interesting. i have an early 72 and had no modifications to do. just plugged the new harness into the back of the new lights and wa la! i didn’t shorten my harness but uses some of the many zip ties that came with it to tuck it out of the way

do you have pictures of your light buckets?

what year did the buckets change? maybe someone upgraded mine but i thought early 72 shared a lot of stuff with 70+


I show 9/71-1/79 using the same Bucket. Earlier would be closed buckets.
 
Was still debating hole sawing the buckets until this morning, have decided to do it. The big “in favor of” factor for this is the idea that part of the value of this upgrade is tool less changing of bulbs this upgrade allows. This was rattling around in my subconscious and only came to light in flash of insight while shaving this morning.

Will shorten harness for cleaner install regardless. Have upgraded my electrical tool kit with a nice new crimper with multiple jaw sets and a couple of kits full of various terminals.

Having an older rig with the terminal blocks on the inner fenders will allow me to make it a little neater by not needing the old plug to plug into for power and I will be able to neatly remove any trace of original connectors.
 
Good job done, congrats guys!

Now I'm tempted to use the kit in my 24V BJ42 (and, if successful, in my 24V BJ45 resto). Do you think that it could be done in a 24V Cruiser, without too much of a hassle? 🤔
 
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Good job done, congrats guys!

Now I'm tempted to use the kit in my 24V BJ42 (and, if successful, in my 24V BJ45 resto). Do you think that it could be done in a 24V Cruiser, without too much of a hassle? 🤔
The instructions do state that the kit works for 24V trucks. I've never tried it, but it should work. I'm not sure if headlight bulbs come in different 12V and 24V varieties though, or if most/all headlight bulbs are different for 12V and 24V systems. I would just check that before proceeding.
 

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