Suppose all the memories in one person were wiped and replaced with your memories. I believe the new body would claim to be you. It would introspect as you might now, and find your memories as its own, and say "I am Dahlen in a new body." But would it be you? If the copying had been non-destructive, then Dahlen in the old body still exists and would "know" on meeting Dahlen in the new body that Dahlen in the new body was really someone else who just got all Dahlen's memories up to that point. Meanwhile, Dahlen in the new body would have capabilities, moods, reactions, which would depend on the substrate more than the memories. The functional parts of the brain, the wiring-other-than-memories as it were, would be different in the new body. Dahlen in the new body would probably behave in ways that were similar to how the old body with its old memories behaved. It would still think it was Dahlen, but as Dahlen in the old body might think, that would just be its opinion and obviously it is mistaken. As to uploading, it is more than the brain that needs to be emulated. We have hormonal systems that mediate fear and joy and probably a broad range of other feelings. I have a sense of my body that I am in some sense constantly aware of which would have to be simulated and would probably be different in an em of me than it is in me, just as it would be different if my memories were put in another body. Would anybody other than Dahlen in the old body have a reason to doubt that Dahlen in the new body wasn't really Dahlen? I don't think so, and especially Dahlen in the new body would probably be pretty sure it was Dahlen, even if it claimed to rationally understand how it might not be. It would know it was somebody, and wouldn't be able to come up with any other compelling idea for who it was other than Dahlen.

The task you describe, at least the part where no whole brain transplant is involved, can be divided into two parts: 1) extracting the essential information about your mind from your brain, and 2) implanting that same information back into another brain. Either of these could be achieved in two radically different ways: a) psychologically, i.e. by interview or memoir writing on the extraction side and "brain-washing" on the implanting side, or b) technologically, i.e. by functional MRI, electro-encephalography, etc on the extraction side. It is hard for me to envision a technological implantation method. Either way, it seems to me that once we understand the mind enough to do any of this, it will turn out the easiest to just do the extraction part and then simulate the mind on a computer, instead of implanting it into a new body. Eliminate the wetware, and gain the benefit of regular backups, copious copies, and Moore's law for increasing effectiveness. Also, this would be ethically much more tractable. It seems to me this could also be the solution to the unfriendly AI problem. What if the AI are us? Then yielding the world to them would not be so much of a problem, suddenly.