OK, so I am a do-it-yourself if you want it done right type of guy. So, I bought a set of 4.10's (10 tooth pinion) for my stock 98 trans am. This car has 40K miles on it, and nothing is broken. So I get the axles out, and remove the diff, next thing is to "tap" the pinion out.
The pinion shaft was rusted solid to the smaller of the two bearings, making it nearly impossible to remove. I was seriously ready to remove the entire rear end from the car. But I got lucky, and after heating the bearing with a bernzomatic torch for about 60 seconds, and POUNDING THE **** out of the pinion shaft with a sledge hammer, it finally came out.
All I can say is HOLY **** was that thing stuck. I completely destroyed the pinion nut and the end of the shaft beating on that thing. But I did win in the end.
To make things even more fun, I still had to beat the bearing races out of the housing.
I eventually won the battle and got my new races and my new pinion shaft installed, but GOD DAMN I have never fought a rear-end like that before!
So if your pinion shaft is stuck, stop hitting it like a girl and get after it!
Now I just hope the pinion depth is correct on the new shaft.....