I have an auto, so figure your HP to do a little better for the same mods.
I have:
1. 12 CM wastegated exhaust housing
2. 3 inch straight pipe exhaust.
3. PW Injectors.
4. Moved timing ahead
5. Adjusted governor stop screws for more rpm ( + 250 rpm )
6. Turned up the fuel screw some (not sure of exact setting).
7. K&N air filter
I did not:
Adjust the diaphragm or no-air settings.
modify the trans in any way.
However, since my transmission bit the dust, perhaps that was a mistake. Overall cost was quite small, and my sig shows an honest 217 HP at the wheels.
While not astounding numbers, a few other 1st gen trucks and even a couple PSD's have challenged me only to find they were sadly lacking the necessities to see anything more than my tailgate
I have a pyro, and when towing, I can get past 900 post-turbo. I have never gotten to 900 otherwise. It takes several minutes of WOT pulling to get there.