I'm not saying that it's beyond my abilities, just that I think it takes a lot of time and the major problem is when you need to add/remove/replace a cable, everything falls apart and "temporary" solutions tend to become permanent.
At my work I do quite a bit of wiring, too. On one occasion we had a neatly arranged bunch of about 200 0,14 mm^2 (~AWG 26) individual wires and it was fine for a year or two, until we needed to rearrange and troubleshoot some stuff. It's been about three years since we finished that, and the wires are still a mess.
On another occasion we disassembled and rebuilt an entire section (with again 100 or so wires). Before disassembly, each wire was taught and just the right length. I labeled each wire before disconnecting it so I can reattach to its proper position later on, but a good deal of them did not fit properly any longer. I had to trim some and splice others (just a few centimeters, but enough so they can't be connected).

I did a decent job on that one, I think, but it took days.