Just wait for some dyno day and jump in for a power run. Only cost like 50bucks for them instead of hiring a dyno (setup + run just for 1 car would be close to 1hr I would imagine, around 150/hr for 4wd dyno). And since 32 is just a fuse away from awd to rwd, I wouldnt be paying extra for awd at all.
Checking the turbo might be hard depending on how accessible they are but injectors should be easy. You can normally tell by the colour of them and jump on Nengun to check what size they are.
Andy: that 10kW is pretty subjective because temperature plays a bit part in dyno and every car is different (not really comparing apples with apples). Unless you got 2 dynos side by side and do the same car on the same day, the claim of gtr's awd power is higher than rwd mode power is quite hard to answer (due to attessa system).
Just for everyone's information, my car was tuned at Gavin Woods' using 4WD dyno and had 340awhp (end of august). But during the dyno day at EFI which was 2wd dyno, it only managed 330rwhp (21st november).