I'm going to say it's valve stem seals due to the amount of oil you can see in the combustion chamber. I bet the shop dunked the head in varsol or another chemical and it just ate away at the seals. I saw this happen to a car at my buddies shop and told him about what it was, and he called me back and said, yep, took the exhaust manifold off and could see oil just pouring from the valve stem area, just dripping down. On the break in note, never had a single ring job smoke at all, zero smoke on break in whether its an SR or any other engine, should not be smoke at all on a fresh build. Maybe like 5 seconds and then it stops quick.