I Own A 1989 W124, I Want To Install All My System Myself But Dont Know Where The Firewall Hole Is At... If Anyone Could Help I Would Greatly Appreciate It... Im Trying To Fit 0 Gauge Wire Thru... Pictures Are Welcomed Haha

-Thanks

Remove cowl panel from passenger side and snake wire upward. It will end up in the proximity of the battery from the other side of the firewall. A very tight squeeze...especially with zero-gauge!

Wish I had better pics of this, but I documented a similar install on my former W124 using 4-gauge wire to the battery post:

Footwell removed. Routed power lead over to the right side:





Engine view with lead arriving at the battery:



Hope this helps.

__________________
2009 ML350 (106K) - Family vehicle
2001 CLK430 Cabriolet (80K) - Wife's car
2005 BMW 645CI (138K) - My daily driver
2016 Mustang (32K) - Daughter's car

At some point, I upgraded from 8-guage to 4-gauge after considering the amp draw from two external power amps...





Along with primary fuse protection.




Power distribution makes things easy to spot and troubleshoot. Add a capacitor if you like it LOUD!

__________________
2009 ML350 (106K) - Family vehicle
2001 CLK430 Cabriolet (80K) - Wife's car
2005 BMW 645CI (138K) - My daily driver
2016 Mustang (32K) - Daughter's car

Check out the DIY I posted on this forum...for a 1989 300E amp install.

Good luck!

__________________
Chris
2007 E550 4Matic - 61,000 Km - Iridium Silver, black leather, Sport package, Premium 2 package
2007 GL450 4Matic - 62,000 Km - Obsidian Black Metallic, black leather, all options
1998 E430 - sold
1989 300E - 333,000 Km - sold
1977 280E - sold
1971 250 - retired

"And a frign hat. They gave me a hat at the annual benefits meeting. I said. how does this benefit me. I dont have anything from the company.. So they gave me a hat." - TheDon

You can also put it through the fuse box. As the wire is pretty thick, using a coathanger to lead the wire is a good trick.

__________________
TC
Current stable:
- 2004 Mazda RALLYWANKEL
- 2007 Saturn sky redline
- 2004 Explorer...under surgery.

Past: 135i, GTI, 300E, 300SD, 300SD, Stealth