Run a wire through the firewall.

Sorry for the newbie non experienced 1990 bronco II question but I want to run a wire ( off road lights) through the firewall. What is the best route to thread the wire through?

Thanks

See if you have room to follow some other factory wiring through the firewall. The other option is to drill your own hole but don't hit anything. then use a rubber gromit to keepthe metal from slicing your wire. Put the switch on the lower half of the dash and run your wire as needed. You can run the wire under the dash on the pass side if you have to drill your on hole. Most likly to ave the most ammount of free sace to pick from.

Ditto what Skitter said....and have a fuse in the + line to the lights. You may want to consider a relay for proper amperage to the lights. Then you can run all your + power under the hood and control the relay with a ground(-) signal from the switch.  Then you only need 1 wire through the firewall and no need to tap power...just ground.

Good luck

Yo James,

Welcome!

 As Mr. SKITTER advised.  If you have an automatic transmission there is probably a rubber or plastic clutch blank cover

I ran wiring through that clutch blank plate and used left-over grommets, etc to seal
 

Wire is sealed w/silver tape over grommet & Caulking Cord 
Rotate pic using blank's bolts/nuts to be lined-up in vertical position.

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Post any TECH questions in a new thread in 80-96 Ford Bronco Tech Support section & keep it limited to one issue. Mainly so that old farts such as I don't get confused.
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Al

If it helps I can post photos of my Installs for my audio systems.

I was really curious about running wires through the firewall too. Miesk5 has about the best idea through the pedals. If you want passenger then you get to remove the heater core, the shroud and probably a lot more. I was hoping the A pillar was hollow where it connects to the roof but it is not so no easy run of wire down that and even if you did, removing the fender will still be almost a requirement so that was out.

On the note of your audio system.... To make my off road lights (just finished yesterday) wiring a cinch, I just wired the power to the power distro block that runs my amps. I added a fuse just after the block before the lights and the fuse is easily accessible when needed. Best thing is all that is done behind my rear seat where a 0ga wire from the battery run underneath the truck comes in and the wiring concealed underneath it, behind the inner side panels, and up above the headliner.

The non-cinchy part was reinstalling all the head liner and inner trim. That stuff sucks and I highly recommend a flashlight to spot your ***** holes through the hole in the part you're trying to put up and then just pray you get em in. Still, WAY better than running through the front unless you go through the existing grommets and/or that blank clutch plate OR just drill a new hole (and use a grommet when done).