This modification will allow you to view you boost at all times with having to convert your MFA reading into useful PSI values. The first thing to do is pick out a gauge. I went with the VDO boost gauge 0-30psi. A stock charger will only put out about 9psi on a good day so if you are not planning on modifying your charger you could get the 0-15psi or even a vacuum/boost which gives you values from 15psi of vacuum to 0 then to 15psi of boost. After all that is taken care of you need to get a t-fitting. VDO gauges do not come with them so I took a trip down to the hardware store. I picked up a threaded t-fitting with two adapters to connect to 1/4" vacuum line and one threaded connector to hook up my VDO vacuum line. I did buy the VDO installation kit that comes with the fitting to hook it to the gauge, 6 feet of vacuum line, and the fitting that connects the boost gauge line to the t-fitting.
With all your hardware taken care of the next thing to do is locate the vacuum line that runs from the intake manifold to the fuel pressure regulator. I bought new line to replace this one along with 4 new hose clamps. Referring to the picture below, I cut two pieces of hose, one to go to the FPR and one to go to the manifold. I connected all these to the t-fitting adapters and then connected the gauge vacuum line. Then I ran it into the car on the drivers side just above the pedals through a hole in the fire wall. You are now done in the engine compartment. Make sure you secured your t-fitting good so it won't move around and work any of the vacuum lines free.
Now for the inside, I opted to make my own gauge panel from ABS and use backstrap for a bracket. I first drilled a hole in the upper left corner of the storage pocket and ran the boost line and wiring for the lights into the pocket. I then made a bracket to attach the gauge panel to the two screws that are already in the back wall of the pocket. I then put the panel in and screwed it into place. The gauges are held in by friction only. I didn't want any exterior screws showing so made the bracket install work with the gauges out. The holes are just right so you have to use some force to put them in. This works great because I couldn't use the VDO back gauge mounting bracket. I hooked up all the wires, pushed in the gauges and that was it.
Some post installation notes:
If you installed a boost only gauge you won't get a reading unless you
are on the throttle. Sitting parked or just cruising down the road
will yield zero boost, don't worry your charger is working just fine.
To really test it get on it full throttle and bring the RPMs into the upper
band, this is where you can see your charger's full potential.