BMW E46 Race Car Build: M54B30 Engine Inspection

How far do I need to go with the M54B30 engine rebuild? We find out!
This rebuild is meant to make sure the engine won't fail at the track this season- not to make sure it'll last another 20 years. That means I am prioritizing what would prevent mechanical failures, instead of power extraction and minimum oil consumption.
I hope that next year I will be able to start doing performance modifications to the engine- this all depends on what is legal for a racing class I can remain competitive in. I don't want to upgrade too much and wind up with an engine that is too powerful, and get bumped into a class where I'll be losing all day- I will get a sense for how to proceed this season when I start competing.