W126 1991 560SEL ignition lock from hell (shift lock wont release).
 

Long story short, my lock barrel jammed and when I tried to unjam it. I broke the key. After about 8 hours with an air hammer (not knowing what I was doing) and killing my dremel. I was able to get the old ignition lock off. Today, I replaced the lock, barrel and steel cover with new parts and everything went back together quite smoothly. However, the shift lock would not release. I can remove the cable from the lock assembly and press down on the pin which would release it but the ignition lock itself will not

Any ideas why?

Failing that, I'm thinking of screwing in a cap over the lock (assuming I can find a cap of the right thread size) so it that the pin is permanently depressed.

Is this a feasible workaround?

Thanks

There is a cam plate assembly that needs to be transferred from the old part. It's a plastic plate about 8mm thick and resides between the ign switch and the lock housing. Have the two steering locks side by side before you begin. I's very easy to confuse the plate's orientation so it is best to transfer it immediately to the awaiting new part. You can confirm its operation by observing the metal contact for the cable release moving outward as you turn the key.:D

After hammering away at it for 5 hours (no kidding) with an air chisel, there really isn't much left of the old cylinder.

If there's a part number for that part, I would love to know it.

Any thoughts about plan B?