Here's a How To for installing an ignition switch. This is on a 70 Dodge Dart
If your gonna do the ignition switch, you may as well do the turn signal switch while in there. That way everything in the column is new..
First pull the wheel...
Pull the turn signal stalk and unscrew the turn signal switch..
Pull the column screws out
Pull the snap ring...
Slide the column apart.
Pull the next snap ring off by the steering lock plate.
Then this little cover. It covers the roll pin that holds the steering lock plate on..
Pull the roll pin out..
Then slide the lock plate off.
Pull the two screws that hold the plate on.
Pull the ignition switch screws.
Let the two switches hang for now..
Now pull the column down
Then the mounting plate needs to come off..The little wire cover comes off
With the mounting plate down and the column hanging you can fish the old wires up through the column. Then the new wires just get fished back down and you reverse the entire procedure and put it back together.