There is a rod that travels through the column and moves the positions on the electrical portion of the ignition switch located further down on the colum. Make sure that is moving to all positions, you could have a bind somewhere. Since you're on a G-body forum, I'm assuming you are working an a G-body?
The neutral safety should be mechanical - moving the shifter on the column should move some pieces down the line as well. Make sure these parts are moving through the range (Drive, Neutral, Reverse, etc..)
It sounds to me like the problem is somewhere in the parts I described. If the key is not physically moving, then something is jammed. Could also be the ignition cylinder - this is a pretty common failure, especially as these cars get older.