Unfortunately, a few days/drives after completing all of the re-installation activities for the new ignition tumbler, I found that the tumbler wouldn’t turn again (argh). Ultimately, the problem proved to be a failure of the mechanism inside the steering housing lock assembly. This is the gray metal L-shaped assembly (about as long as your outstretched hand) that the ignition tumbler fits into, secures to the steering column, and which locks the steering wheel. Once I had this part out of the vehicle, I could clearly demonstrate that it was the internals of this part that had failed and were causing the steering wheel to remain locked when it shouldn’t have been. This is not to say that the old (original) ignition tumbler was in fine shape. My summary of this project is this: Do not be fooled into thinking (as I was) that after more than 20 years of use, only the ignition tumbler wears. My experience has proven that the highly complicated steering housing lock assembly (and its operation is a fun project to analyze) wears just like most everything else on the vehicle. Now that the ignition tumbler and steering housing lock assembly are new/replaced, everything is tight and smooth – probably how it was in Dec. of 1982 when they built/assembled the vehicle. Good thing all of this lasts so long because this is quite an unpleasant job, ESPECIALLY when you cannot turn the ignition key anymore (my case). And this is coming from the same person who replaced the cylinder head/head gasket on this same vehicle.