I’m trying to find a way to install these electric gauges without butchering the original dash harness. Is there a way to run them through the fuse box without having to cut into the dash harness?
Are you just trying to get 12v for power or are you trying to run new wires from the new senders to the gauges? If you need to run wires from senders to gauges, you can just use these Packard terminals to run the wires through the bulkhead connectors behind the fuse box. There are quite a few empty cavities in those connectors. It beats drilling holes through the firewall.
Right in the center of that box are the extra terminals for added accessories. The one on the bottom is ignition, the next one up is hot in accessory and I can't read the other two. GM used to just use wires that plugged into those terminals when they added accessories like power windows, power seats, and power locks. From the factory, they would just several together in series if the car had a lot of options. Are those upper terminals melted? You may need to address that before you have real problems! The instrument light terminals look rusty. It may be time to upgrade, or at least replace the damaged terminals.
I spliced the power to the stock radio to power a few things. It was in a convenient location and is also switched by the ignition. Then I put all thicker supply wires for the sound system etc through the passenger side fire wall. There was a rubber grommet for vacuum lines there anyway, so didn't have to drill. By doing this all non-stock electricity ends up on one single side of the vehicle so the wiring becomes easier to follow and also stock restore if anyone wanted to.
