as a noob can I ask what the valve guides do and is this the same as the timing chain guides. and you mention a TSB(?).
The repair manual I would be highly interested in, do you have a pdf you can send or something? this is the dealer pic of my engine, can't see the corrosion on the top of the head here but it is evident when close up. only had my car several months and driving it just a little until I get the issues all fixed;

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