wheel offset

I have a 1989 lx 5.0 coupe. I am going to change the front hub and spindle to a 1995 set up. I will also change the rear to a sn95 rear. I want to go with a 17X9. What offset do I need to have for the front? and the rear? I was thinking of going with 255/40-17 tires I want to have everything work together so that the project will go smooth. I need to make the change over a three day week end. The car is stock height.

That answers the question of the rear of the car. I still ned the offset on the front of the car with the sn95 conversion. I want to thank everyone for their help.