Has anyone sussed what the two huge metal plates are for? My guess goes back to a mate who made an electronic gizmo and showed the prototype to his boss who just weighed it in his hand and said “Add a pound”. Nobody pays for lightweight kit unless it’s a necessity!!

The replacement board that I’ve got has not got a grey plastic flip down ribbon cable retainer! How do I swap one from my old board?

Apple had a replacement service for late 2011 15inch MBPs which cured a mysterious fault which rendered it un-usable. I had mine fixed at a Genius Bar but my mate who also bought one has missed the program and has a completely dead MBP. Am I right in assuming that following your procedure above and using one of your logic boards would fix this?