is it tough to replace an ignition lock tumbler?

i have a 300 SD mercedes which was made during the 70's. i couldnt turn the key to the start position and had to knock the whole thing out just so i could hot wire it to get it home. Is it tough to replace a tumbler with a new one? Does it matter what year it was in? if so are cars before the 90's the easiest to work with? can you give me step by step instruction or show me a site that will help me with it? What is the exact year? discretesignals wrote:What is the exact year?

1980Car Repair Talk's forum.