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To redo the rotten wiring on my truck I bought an American Auto Wiring kit. I have the engine bay wired and am working on the cab wiring. I have the fuse block screwed to the firewall near the steering wheel and I need to route the harness to the other side for the passenger door switch and courtesy light. I could drill holes across the firewall along the top to hang brackets but that seems sacrilegious to me, I felt physical pain just mounting the fuse box .
The question I have for y'all is what would be the best way to run wires under the dash?
For future reference, rather than drill through your firewall to mount the fuse block or any other underdash item you may want to fabricate a block and glue it to the firewall. Here is a pic showing how I mounted the e-brake, fuse block, gas pedal, and MSD box in this manner.
Hotrod350
I replaced the hood hinge bolts with all thread rod so I could bolt in an angle iron frame along the inside top portion of the inner firewall. The all thread rod allows me to use nuts to secure the hinges on the outside of the firewall and use nuts to secure the angle iron framework on the inside.
With the angle iron running across the inside, I can tie up all of the wires that route to the passenger side of the cab.
Hotrod350
I replaced the hood hinge bolts with all thread rod so I could bolt in an angle iron frame along the inside top portion of the inner firewall. The all thread rod allows me to use nuts to secure the hinges on the outside of the firewall and use nuts to secure the angle iron framework on the inside.
With the angle iron running across the inside, I can tie up all of the wires that route to the passenger side of the cab.
Hope this helps
Dan
Dan that is an ingenious idea. How do you attach the angle iron to the nuts? Does the all thread stretch the length of the cab or is it a short piece?
I cut the all thread long enough to allow nuts to attach the hood hinges on the outside and the angle iron on the inside. I welded two pieces of angle to the large angle at a 90° (angle) and drilled holes to mount to the all thread. Got the idea from a member here on FTE.
good info here in this thread... here's some other options... this cross piece isn't my original idea, I copied someone else's design and it worked out great
fuse mount plate
cross bar for plate... screwed to kick panel brace
tube used to control wiring and mount accessories, there will be a relay
board mounted here also for the doorlocks
Cable tie mounts work great and will even adhere to Dynamat.
I agree these work very well. Home Depot sells them by the bag.
Also Scotch dual lock is great. It is like super velcro and very strong. It was designed for use in the aircraft industry. You can use it to hold control boxes, wiring harnesses or trim panels in place. The nice part is that you can remove and reinstall the part at will again and again without losing any strength. It doesn't get full of fuzz or wear out like velcro does. More than 1" on the back of a controller will require a screw driver to pry it loose -.3M Dual Lock. That link is to Amazon but I got mine at Home Depot.
I like Charlie's idea of gluing things to the firewall and using Pete's idea of the dual lock on items like the fuse block. Makes for a no tool removal so you pull it down to add circuits, replace fuses, etc.. and then replace.
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