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Which H1-4 Harness?

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Old Feb 11, 2026 | 12:13 PM
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St. Jude Donor '25
Default Which H1-4 Harness?

I'm looking to install the harness that leaves the low beams on when switching to high beams. I see several vendors offer them. I'm looking for one that will install with no modifications.
Here's what I don't want to do - this review excerpt from Amazon:
The HI-4 harness LED conversion works well but you need to slightly modify it to fit. First you need to widen the bolt hole in the harness. I used a 15/64th drill bit and it worked perfectly, if you don’t have a 15/64th bit use a 1/4 bit. Secondly, you need to add a spacer under the harness so it will fit properly. I just used a stack of washers as a spacer and it works fine. Thirdly, you need to modify the fuse box lid. I had to cut some of the fuse box lid to get the kit to fit properly with the wires from the harness. Use a grommet or electrical tape to prevent the wires from damage.

So who sells the best bolt on harness?
Thanks!
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Old Feb 12, 2026 | 06:08 PM
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Default Sharplight Innovations

My go to for C5 lighting. 1st rate products and customer service.

https://sharplightinnovations.com/sh...s/hi-4-harness



Last edited by vette4fl; Feb 12, 2026 at 09:07 PM.
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Old Feb 13, 2026 | 06:21 PM
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Six7390gt
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Default

Originally Posted by vette4fl
My go to for C5 lighting. 1st rate products and customer service.

https://sharplightinnovations.com/sh...s/hi-4-harness

Thanks, I've got one on order
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