1) Awesome, congrats - I think my E46 M3 was maybe the most fun track car I've ever owned. Mine was full interior and full weight to boot
2) Do Rod bearings? - you're saying this car never had the recall? Or are people running into issues after extended mileage on the updated spec bearings? I saw the bearings that came out of my car and they were really clean, but my car wasn't tracked prior to the recall either.
3) You don't have to go crazy on the setup. the one you propose plus ground control bars is the ticket. Mine was even more simple and the car was still plenty fast and wicked fun to drive.
PCA Nationally Certified Driving Instructor