I did lots of research on how to install a boost gauge into my drivers side centre vent gauge.
Sadly most of the links had been deleted or spent too much time on how to remove the eyeball vent and then showed the boost gauge fitted.
Removing the Eyeball Vent
There seems to be two ways of doing this. First there is the credit card trick which can be found on Youtube.
https://www.youtube.com/watch?v=DZUrH4C7EL4
The second is the string trick. Where you thread a piece of string through the eyeball vent and pull hard. The vent should pop out.
I say "Should". Mine didn't!
The way I got mine out was to do a combination of the above two methods together. It worked a treat and it just came out.
Pull on the string whilst working around with the credit card.
Something to note is that I removed my satin ring before removing the eyeball vent. I did this by pushing the credit card around the satin ring and it just fell off.
Now you have to remove the black ring from the top of the vent.
You do this by using a flat blade screwdriver and push on the locating clips around the top.
Don't worry if they snap a bit the ring is all you want.
The gauge I bought was a Dragon Gauge and it came with a metal bezel fixed to the top of it. This had to come off and was very easy to do. A screwdriver loosened the the bezel and it came off.
The bezel holds the smoked plastic lens on. Put the lens in a safe place for later. The lense sat on a plastic holder that was cream colour. I used a permanent marker to make this black.
Push the black ring on to the gauge. It fits a 52mm gauge perfectly. Now super glue the lense holder on to the top of it.
And you will end up with something like this.
HOW TO PLUMB IT IN
If you look into the vent hole you will see a nice gap where you can push the vacuum tube and wiring down.
Now to get the vacuum tubing from the engine bay to the cockpit.
This was actually quite easy but only after much consideration.
There is a thick soundproofing sponge on the inside of the cockpit wall. So any small gromit removed still made it impossible to get the tubing through.
Anyway on the passenger side there was a big rubber seal. I removed this and then found there was accessible holes into the cockpit through it.
I drilled a 10mm hole trough the rubber which I could feed the tubing through.
Now to use the special equipment!
The special equipment is a net curtain wire. Push it through the hole in the rubber and feed it through. It will appear in the passenger footwell.
The gauge came with some clear nylon tubing but I had some red silicone tubing I wanted to use in the engine bay so I used a combination of the two.
Now here's the clever bit. The curtain wire was just the right diameter to push the clear nylon tubing on to it. Do this and then pull the curtain wire in the passenger footwell to feed the nylon tubing through.
Now detach the curtain wire and feed it trough the gap in the vent hole.
Aim the wire towards the passenger footwell.
It should feed through just fine.
Reattach the clear nylon tubing to the curtain wire and now pull the curtain wire back out of the vent and it should feed the clear nylon wire through the vent gap.
For me the electrical wiring was very easy.
I pushed the wires through the vent gap and as I have a single DIN Sony stereo as standard I just pulled this out and found the Earth and Switched Live going to the stereo and tapped into them.
Back in the engine bay I used a hose connector (luckily I have a fishtank and had an air hose connector going spare) to connect my red silicone tubing to the clear nylon tubing. I then pulled the clear nylon tubing into the cockpit until the connector was hidden.
I ran the red tubing over the coil pack and connected it to the manifold. I cable tied it up all neatly.
Back in the car. Cut the nylon tubing but be generous to allow for removal/servicing and a non-kink tube.
Fit the tube to the gauge and test it all out to see if it all works.
If all is well push the gauge into the air vent hole. The black surround ring should be a tight fit. Mine was so tight I didn't need any glue.
I then superglued the smoked lens to the lens holder and finally glued the satin ring to the lens holder.
All Done.
In Hindsight there's only one thing I may have done differently.
The satin ring has a very small gap where it isn't seating flush to the dash. This is because it's resting on the lens holder and it's making it a bit proud from the dash.
What could have worked would be to remove the lens holder and glue the smoked lens directly to the satin ring. Then if the satin ring is flush with dash just glue the ring to the dash. This would only work if the gauge in the black ring surround is set far enough back to stop the lens touching the gauge needle.
If you do the same install it maybe worth a try.