Fist thing’s first - you need a boost gauge!
Luckily, I had one lying around in my RS Turbo!.

I chose to fit mine in one of the A-pillar pods that I got a company called Nomad to produce for the Fiat Coupe.

     
   
 



The boost gauge reads the pressure within the inlet manifold, so needs plumbing in to it somehow. I found the best place to be the connection for the DV (dump valve), located between ports 3 and 4.

This just pulls off to reveal a perfect take-off point.

For the 20VT engine, check out the top two images HERE.

      
   
 
Connect the hose that you just pulled off to the T-piece, then connect the T-piece to the manifold take-off point using a small piece of rubber hosing. 		     
   
 
This picture shows the location of the take-off point on the 16VT inlet manifold more clearly. 		     
   
 
Now connect the length of hose that will run to your boost gauge to the T-piece. If the length of hosing is flexible nylon tubing like mine, use another small length of rubber hosing between the tubing and the T-piece. I used small hose clamps to ensure a tight fit, but nylon cable ties should be fine.
     
   
 
This is the hardest bit - getting the hose into the cabin. I removed the windscreen wipers (13mm bolts) and the plastic trim below the windscreen (self tappers) and found a grommet with a cable already running through it. I pushed the grommet through the hole, then threaded the nylon tubing through.

The easier way to do it is illustrated in pictures 3 & 4 HERE.		      
   
 
I found the tubing above the drivers footwell, then threaded it up the dash, behind the A-pillar pod, then connected it to my boost gauge using another small piece of rubber hosing and hose clamps. Then consult the instructions for your boost gauge, and connect up two wires for the lighting. 		     
   
 


Remove the drivers-side panel of the dashboard. This is held on by a small plastic nut at the bottom which is accessible from the footwell. The panel then simply slides down, away from the bulkhead, then out.

You’ll see a large red plug at the back of the light-dimmer switch. Remove this, then, using either two Scotchlocks, or the ‘jam the wires in’ method, connect up the live feed wire to the top red/yellow wire, and the earth to the bottom black wire.

 

      
       
That's it - job done!
You should now have a boost gauge that shows the PSi/bar you're turbo is shoving out. You'll even be able to see it at night, with the added bonus of being able to dim it with the rest of the dash lights!

As a precaution, go over all of the wiring/tubing/hosing you've just added and make sure it is all secured, especially if you've run it through the hole/grommet suggested. The last thing you want is the windscreen wiper mechanism slicing through your handiwork!