Those are three seperate areas, so the order is up to your personal preference. I would suggest, however, that once you start on an area, you finish it, and then keep all of the stuff for that area together, but separate from the stuff for the other areas. Nothing worse than searching through 200 bags of fasteners and small parts to find the specific one you are looking for.
When bagging and labelling the fasteners and small parts, be as descriptive as possible, not just a scap of paper that says "Seat" or "Dash". It will pay for itself when its time to put it all back together.
Digital video cameras using mini CD discs, are cheap. If you dont have one, factor one in as part of the cost of restoration. When you disassemble something, make a closeup video of it, showing first the part, then the entire disassembly process, the nuts, bolts, etc. Document everything with it. Visit the body shop often, and document the progress there. The nice thing about a digital video camera, is that it creates a dated index clip using the starting frame of the clip, so you will have a list of visual cues identifying the clips. When its time to put it back together, play the disassembly clips in reverse, and you will have your own custom assembly manual.
BTW, the videos not only document the disassembly, restoration, and assembly. They can also be invalueable if some type of problem occurs, or you need to file an insurance claim. Lets say that you visit the body shop every week, for ten weeks, and there is no progress on your car, then the body shop wants to charge you for 10 weeks of storage. Or the body shop charges you for something that did not need done, or parts wind up missing or damaged, and the body shop denies any knowledge. You now have undisputable evidence that you can use to keep them in line, or to use in court to uphold your case.
