My pickup was losing power and oil. I found the timing chain issue in these forums and caught the problem before the coolant and oil mixed.

I ended up removing the engine for cleaning, inspection, head gasket replacement etc.

While working on the head, I removed the back plate for the EGR. One of the bolts sheared. Removing the bolt proved difficult and in the end, my extractor expanded the hole, cracking the head and boring the bolt whole all of the way through.

This still didn't remove all of the bolt, but I'm not sure if this is salvageable or if I need to replace the head to avoid leaking coolant.