Well, the DIY is not perfect. I left out a few important details which I neglected to do myself. As stated, I am not a mechanic.
The additional inputs have been great and very informative. This is why I posted a DIY so that I can get feed back. Fortunately for me, the car has not missed a beat since the spark plug changed. Thanks to Tischer for great OEM products.
In addition, I see that a few things have changed-like different spark plugs are now avaiable for our 06 e90. I will definitely refer back to this for the next plugs change (if I end up keeping the car way beyond 150K miles - given that it continues to behave well to my liking
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