Totally non-invasive wire run found. Note this is a right hand drive and pics will follow.

I have been following this thread as I have been dragging my heals on the amp install as I didn't want to cut the firewall or the main harness grommet. Decided to bite the bullet today and make it happen. After a bit of trial and error, I found that the fresh air inlet sits behind the shock absorber access cover on the passenger side. I was able to run the cable down the fresh air inlet to just above the pollen filter, I was then able to push it through the foam gasket above the fresh air/recycled air door and into the cabin. I have used 4 gauge and it fit well but I expect it would be easier with 8 gauge. Note that there is a metal lip just before the inlet so I have covered this with some tape and the cable with some split tubing then taped that down to reduce the rubbing.

I had planned to put my old amp under a back seat but have bought a new 5ch with line inputs which will now be place in the spare tyre well as there is enough space for it next to the spare.

Earth will be the factory earth point behind the rear quarter vanity panel.

Will post pics once all is done.

 

Factory earth in rear quarter to be used. Glass wool used to aid with insulation.[/URL]

Power wire covered in split tube entering the cowl, I would like to believe that one of the engineers at Honda knew this would go on and indented the lip of the cowl with a space just the right size for 4 gauge... Should have taken a pic before the split loom went on. [/URL]
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No flash on my phone but the cable enters the fresh air vent here.
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Cable entering the cabin. It would be easier if it could pop out the opening but then would fowl the fresh/recycled air vent but not very hard to pop it through the foam seal.
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