I don't think it's nearly that simple. We need to know what matters (simulating everything is impractical) and we need to be able to do it without losing the information in the process--you could record the surface easily enough but how do you get the information beneath without the brain dying and decaying while you're doing it?
So, for the most part it is a function of making an identification of the qualities of a given neuron. At it's basic level, the neuron is just a machine with various levers that bias it one way or another. If you look at the mechanics of neurons in general, and the mechanical elements of any given neuron specifically (by it's chemistry, methylation, and so on), it is just a matter of properly tagging those qualities. It doesn't need to be seen in real time as long as you can figure out sufficient minutae to correlate what is seen to how whatever is being seen behaves in general.
At any rate, I'm talking full destructive scans: turn me into a meat popsicle and shave me down layer by layer with a diamond razor and feed each one through an electron microscope, makes no nevermind to me. As long as the model for reconstructing and simulating the resultant data is sufficient, I'm not too bothered. If they get it wrong the first few times? Well, I hope they save the data at least. That's actually one of my contracts with myself, to not shy away from at least trying to evaluate whether I can handle and live with particular experiences.