Honostly, I don't think they had it hooked up. On a turbo car, it goes lean before hitting boost.
I'd find another shop to dyno your car. Find someone who knows what they are doing.
As far as vacuum leaks, go around with a spray bottle of water with a touch of soap in it. The bubbles generate will pinpoint leaks better.
"As the Z32 gets older and decreases in value it becomes affordable by lower income and often less desirable people whose tastes reflect their personality and social standing.- Marshall 17:37:05 10/10/03