Well thanks. Now that I have extracted this information from you (quite painfully) I can tell you that the stock offset of a 7 series is 24mm.
So you will need 14mm spacers to fit the calipers if you retain the standard caliper to carrier offset. Which you won't be because you are apparently skimming 3mm off the faces of the calipers.
Which for somebody of your suggested engineering knowledge shouldn't have been too difficult to work out.
That said, and all **** taking aside...
Why are you **** arsing about fitting these calipers? What are you building? And what master cylinder are you using? Why do you think you need 70mm clearance? Have you not thought that these MONSTER calipers will hugely over heat the discs and cause consant pad issues, and constant boiling fluid?
Going to all that effort and keeping 312mm discs is frankly retarded; and I have no issues in telling you that. Why not just fit LCR Brembos or GT Junior calipers?
Genuinely intrigued why you are going to all this effort.