I do not know what (if any) similarities exist between a 126 and 123 ignition, but my problem was that the shaft between the tumbler and the switch broke. This turned out to be a very BIG PROBLEM because the ignition has to be turned to unlock the connector from the switch. I spent three hours chipping my switch apart to release the connector. I had over fiver hours in the whole project. I recommend that you check for this.