Mercedes Benz repair: MERCEDES-BENZ, 300sd mercedes benz, mercedes benz

Question
I own a 1980 300sd MERCEDES-BENZ that the ingtion has recently stopped turn. I thought it might have been the key so I bought a new one but still nothing. I have noticed that when I change it from drive to park it doesn't click it park could this stop the key from turning?

Answer
How not to remove the ignition lock! Butchery at its finest.
http://www.mercedesshop.com/shopforum/showthread.php?t=148451

Ignition Cylinder Tumbler replacement; mixed diesel/gas
http://www.mercedesshop.com/shopforum/showthread.php?p=1065596#post1065596

Ignition Cylinder, Switch, or Housing?
http://www.mercedesshop.com/shopforum/showthread.php?t=145832