I had a friend that was going to do the Fiero swap back in 1998 until he found out what the price tag was on a Northstar motor. It's a great motor.....when it's running. Very odd design too, the starter is underneath the intake manifold. If I remember correctly, the water pump is on the back of the motor (side where the transmission is). I'm also not a fan of the 4T80-E transmission. They don't hold up to abuse.
I remember racing a turbo'd Civic in my STS and I beat it by 3 car lengths to 75-80 mph, then we saw some fuzz and backed off.