Transferring large amount (84 million rows) of data efficiently
I would add that, however you decide to approach this, you'll need to batch these transactions. I've had very good luck with the linked article lately, and I appreciate the way it takes advantage of indexes as opposed to most batched solutions I see. 

Even minimally logged, those are big transactions, and you could be spend a lot of time dealing with the ramifications of abnormal log growth (VLFs, truncating, right-sizing, etc.).

Thanks