5 minute DIY - Installing a boost gauge in 300SD

Really, this install could not be easier.  I picked up a cheapo boost/vacuum gauge from Harbor Freight for about $20, came with about 3-4 feet of vacuum tube, a plastic tee connection, and some crappy bracketry.  Not only was it cheap, but it is extremely cheesy as well, allowing the user to select any number of colors to look super cool!  Being that my SD is already cool and particularly riced-out on the inside, this fit perfectly within the decor.  The easiest place to tap into the boost is with the overboost protection line running from a banjo bolt on the intake manifold over the top of the valve cover into a little cylindrical gizmo on the driver's side fender.  What this does is it monitors the boost and sends a signal to the ALDA which eventually regulates the amount of fuel going into the injector pump, thus limiting boost.  However, most turbos 30 years old are not putting out a whole lot of boost - thus the case for a boost gauge.  While you're working on the boost line, it is a good idea to unscrew the banjo bolt (don't lose it like I did last year...) and give it a really good cleaning.  They can get clogged up with soot and stuff over the years which will limit the performance of your car as well as render the boost gauge inaccurate.  Furthermore, it only takes 30 seconds of your time and is a good practice every couple years.
Anyways, regarding the gauge - I tapped in right before the overboost protection solenoid in order to give me as much vacuum hose as possible going into the cabin.  Unfortunately, being a piece of crap, the tee that came with the gauge broke almost immediately.  Luckily I had another tee on hand that fit a little better, and used that to tap into the line.  A boost gauge such as this requires the vacuum/boost hose to go through the firewall into the passenger compartment, and there are a few ways to do this.  The tubing that came with the crappy gauge was very thick and I didn't have any spare hard tubing available.  Therefore I chose  to route it in the same grommet as the hood  release cable, between the fuse box and fender.  There was a plugged space available (not sure why...), all you need to do is unplug it and route the hose through. A good trick is to stick an unbent coathanger in the tubing to stiffen it, then route it into the cabin.  That way, the flexible tubing won't bunch up and you won't have to crawl uncomfortably around the pedal area. 
You can mount the gauge wherever you please, but the most logical for me was right under the ignition tumbler, since it was out of the way yet still visible.  There is a trim piece that uses a screw along with a trim clip to secure against the top dash.  This was solid enough to mount the gauge.  I had some 90* steel brackets left over from an electronic drum kit I made, so I bent one to shape and screwed it in.  Attach the boost line to the back of the gauge and you've got a working gauge.  As far as wiring, I installed a radio at the same time, so I decided to use the 12V+ and illumination wires from that to also power the gauge LED.  The ground just went to a chassis spot.  In all, it took me longer to write this than it did to  install the gauge in the car.  Any questions just comment and I'll be happy to answer.

Pics are still coming.  I had written this a while ago, never got around to posting it, but unfortunately my camera is MIA :( 

DIY w126 cupholder part 1

There was a day back when cars actually did NOT have cupholders.  My Mercedes, both w124 and w126 like to constantly remind me of this fact practically every day.  Yet, there is a clunky pull-out ashtray and cigarette lighter that almost never works, go figure.  Let's exchange one for another, shall we?

Taking apart the old ashtray
Taking the old ashtray apart revealed a couple things...1 - that it was incredibly simply designed with a plastic tray and pop-up lighter on a spring.  2. The front wood was just glued on. 3. It was asking for a mod.
You can see that it simply slid on rails, here is the outer housing:

Therefore, you could make a thin board-like structure to slide in and out--this was the idea behind my design.  I wanted to keep it pretty simple, no metalwork, no hard cutting, nothing too crazy.  Here's what I've done so far:

1. Cut out a template from cardboard

Traced out the circles, I used a coffee mug as a template...then cut those bad boys out!  Here is the rough idea - it should look similar to this once finished (without the tear):

Next step was to cover everything in either fabric or fiberglass.  I had an old flannel sheet lying around and flannel happens to be PERFECT for this type of application.  A lot of custom audio guys use flannel soaked in resin as a base for custom speaker boxes.  It isn't perfectly flat, but will be decent once the resin soaks the fabric:

Next, mix up the resin/hardener to specification (1/10 can of resin = 1/10 tube of hardener) and thoroughly soak the whole thing, however not leaving any excess resin floatting around.  Stick a sheet of release paper (I use wax paper, it isn't too bad) under it so it doesn't bond to whatever surface it is drying on.  Here it is, soaked in resin:

Right now it is curing.  Part 2 will be following a good night's sleep and 8 hours of work.