If you place the EGT next to one exhaust outlet from only one cylinder you will only get the temp for that cylinder.
Personally I would aim to place the EGT where all the gas streams are merged.
Then you get a good average.
Some might say it doesn't matter, Just makes sense to me.
Somewhere here would be good....

And before the turbo is ideal......As this is the true temp your engine is producing and what your turbo is being exposed to.
The issue of probes breaking and stuffing the turbo and far and few between....
As for gauges, I priced up units here in NZ and they were really expensive.
Went for a digital gauge from the states...Can set alarms to warn you to back off.
And use them for something else if you change vehicles etc etc.
http://www.auberins.com/index.php?main_ ... 3dd748c49aOthers have also done this...
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Have fun....