It takes about a 20 working hours to assemble a Mendel Tricolour
http://www.youtube.com/watch?v=OMFWg96irLE
Really long,but the video has great music 
It’s a whole process. I think it could be used as manual in some cases. About music - all soundtracks are from my VideoEditor))
I mean 20 hours seems a lot for assembling a 3d printer from a kit.
I can see that wirings is taking a big piece of time.
I don’t remeber exactly how much time i spent wiring & soldering. But it was a huge amount, especially counting that was a Mendel Trcolour with 3 extruders, 3 hotends, and 2 controllers. Actually 1 minute of this video equal to 30 minutes in real time mode.