turbo WAS installed currently enjoying 7k of happy boosting in my 15k baja.
so far the parts i've found that don't work are
kartboy wrx shorthrow shifter (though a machine shop will be fixing that shortly)
large intercoolers hit the brake resivoir and make the peddles vibrate you have to make some custom bracket to keep it off the booster.
Large intercoolers when pushed up off the brakes resivoir hit the hood. I ended up "modifing the hood w/ my dremel" two minutes work and NO MORE vibrating noises cool
make sure the aftermarket exhuast you use does not bump the rear diff when going in reverse. Very annoying. though for the record the sound it makes is SOO cool! even before the turbo it sounded like a pissed off rally car.
make sure you get a ecu pinout Before adding any piggy backs i would reccomend you save the time and engergy and just get a standalone put in when you get the turbo.
walbro fuel pump has a hard time fiting. custom work needed to be done.
other than that 2.5rs parts all the way (turbo wise i'm curently looking into an offroading suspension package (agx's and higher spring rates))
good luck to you. Baja t's are fun!