What is blatantly missing are the instructions for reassembly, as the odd step or two does require the pieces in the right position, and just how tight the screws should be etc.
I do have an engineering background and some experience in such things, so I was of course less nervous than some might be!
Well if you have an engineering background you must know that all screws, nuts and bolts must be tightened to the point where they make a sickening snapping noise. Then tighten it 1/4 of a turn more and you're fine!
In all seriousness, if you have a set of micro screwdrivers, the screws should never be tichtened more than you are able to achieve with the ribbed screwdriver between your fingers. Never use an extension or pliers to get more torque. All proper hand tools are designed with torque arms based on the average person's strength. Obviously this doesn't apply to adjustable spanners. Oh, and when in doubt don't overdo the torque but use a little loctite (the easy to loosen type).
5D3, 5D2, Sony α6000, G16 | EF: SY14/2.8, V20/3.5, 28/2.8 IS, Ʃ35/1.4, 50/1.8, Ʃ50/1.4 EX, 100/2.8L IS Macro, 16-35/4L IS, 24-105/4L IS, 70-200/2.8L IS II, 1.4x II, 2.0x III, 70-300L IS, T28-300 Di VC PZD, Ʃ150-600 DG OS HSM S | E: SY12/2, 35/1.8 OSS, 16-70 ZA OSS, 55-210 OSS, SY300/6.3 ED UMC CS