You dont need any gauges Cause they dont really do anything but tell you what is already happening. I would suggest a boost just so you can watch it peak and look cool. Other than that maybe an air fuel since thats what a Turbo changes.
look cool?
What are you talking about?
When you Turbo a car, some gauges are very critical.
Especially boost gauge and oil pressure gauge.
A/F gauge is no good without a wideband O2 sensor.
You might wanna consider EGT (pyrometer) instead.
You can either put the probe in the hottest runner
(usually the one that get highest amount of air)
or in the downpipe. Temp reading will be a bit off
when you put it in the downpipe.
I would suggest, boost gauge, oil pressure, and EGT.
If you install the FPR, it's a good idea to get the fuel pressure gauge also.