Lots of pictures and lots of notes.

You'll be fine.

LTG : )™

Measure those tall posts on the topside under the ramps/coffin. There a bunch of different lengths.

and when you think you have taken enough pictures, take more... you CANNOT have too many...

If you're taking a close detail picture be sure to follow up with a picture zoomed out some so you can orientate yourself later on.

Invest in a Gopro video camera, strap it to your head, shoot the video, then reverse it. Makes things simple.

a good idea... even a cheapo one will do the job...

What a great idea, I love it! Is this really practical, watching the reverse of the video when you are putting it back together?

And, how many hours of footage are we talking about here?

I'm assuming you mean to wires to the backbox? I think you'd have a much easier time if you disconnected the connectors. Just snap a photo of two of where each one goes. Impossible to have too many photos. The connectors seem daunting because there are so many, but they fall back into place fairly well and process of elimination is helpful.

One thing I started doing is keeping plastics in the same bag as the posts and screws that goes with them (same thing with the coils/hardware). That's helped me. Otherwise, lots & lots of pictures and labeling.