Where can I easily route some wires and Vacuum Line?
 

I am planning on installing my little pod of gauges I made, which has Boost, Oil Temp, and a Voltage Gauge. I was wondering where I could route the tube for the boost gauge, as well as a few wires for the oil temp gauge, where is the best path to get them out into the engine compartment? I am installing the cluster where the ash tray was, this is on the 1982 300SD. Also, what would be the best place to splice in the line to the boost gauge? Right by the manifold? Or anywhere along that line? I have no clue where I can route these wires and tube, so I need some help here....

anyone....? :confused:

I put mine through the same hole the AC refridgerant goes through...the blue line above the go pedal.

What about the firewall plug that the vacuum lines go through?
I had a few capped, unused holes in mine (not all used by vac lines) which I wired through a couple toggle switches.
Just snip off the tiny plug end, and feed through; comes out a great place under the dash for guages.

Do you mean the plug right next to the fuse box? I see a plug with about 2-3 vac lines going through it, and the rest are these little rubber protrusions....do you mean if I cut off a protrusion and push wire through it will come out somewhere inside? Where does it come out???

Ok I have it now, I took the whole interior apart on the drivers side.... :eek: I think I will take out my cruise amplifier and resolder everything while I'm at it, today has become project day :D :D

That is exactly what I mean.
Just look under the dash, above foot pedals, to see where the vac lines come through. Very accomidating.

I ran a set of twisted wires for my Oil Temp Gauge (have yet to hook it up, I'll do that next time I change the oil....) and a rubber vacuum line for the boost gauge, which I did splice in and hook up, then took it for a spin, at full accelleration/pedal I get almost 11 bar of boost! :D! Good stuff, Now I just need to make a nice face plate to hold the gauges, and to hook up the voltage and oil temp ones. I didn't mess with the cruise amp, that thing is HUGE, and how does one get it out easily? the screws are so hard to reach that I just gave up for now....I'll save it for another day. I noticed the very well designed brake-light switch on these cars while I was under there, comparing it to the one that FAILED on our caravan at about 65,000 miles, there's no comparison. The van one failed and the lights would stick on, even with the car off, draining the battery. Ironic, if you leave the headlights on in the van, it will turn them off after about 15 minutes to save the battery, but it does not do it when the brake lights stay on, rather typical. This turned into a rant against our non MB car....wups.....:D :D

Also, for others viewing at a later date, you can run the wires and whatnot through the fusebox on a 300SD (w126) as the fuse box has MANY extra holes of varying sizes and also, where it enters the cabin, has a HUMONGOUS hole that you can easly get things through the firewall.

Doing this means removing the two screws on the top of the fuse box and lifiting it up to reveal the rats nest underneath.

This is what I did on the SD to install a boost and pyrometer line into the cabin...worked out quite nicely :)

Here's a picture of where to route vacuum and wiring through. The unused spots have small caps that simply pull off.

http://www.ultrahot.com/glowkit/gpk_09a.jpg