I am trying to re-key my 1975 ignition lock, how do you remove the tumbler? I have removed the alloy casting but cannot see how the lock can be removed!

The later ignition housing became more tamper-proof in 1975. here is a Link to remove it

Remove the steering wheel, wiper and indicator switches. The switches push through the column housing from the rear after unplugging the harness connectors, Be careful as these parts can be brittle from age and the accumulated dirt can make them difficult to move at first but after some gentle jiggling they should slide forward readily.

Once these switches are removed you should see two screws holding the barrel in place, remove these and the barrel should slide out. Hopefully the steering lock is not locked as it needs to be unlocked for the barrel to slide forward.

Good luck,

You've got to drill a hole in the casting to access a leaf spring that has to be pushed in to release the tumbler. Can't describe the location.
Been a long time since I've done it.
Someone will probably chime in.
Or....Google it.

DO NOT attempt to rekey it yourself. Have it done. 75-76 locks have a set of cam rollers instead of the slot type. Lock will be a nightmare trying to get back together.

There is a square hole where the triangle-ish steel piece slides in. Push that in to depress the leaf spring type retainer. Then it will slide out with some effort. The key is supposed to be inserted and turned but I've had mixed results. The switch must be removed from the back first.

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