Answers to your questions:

1) Yes it is the kind of fish scale for weighing fish. You need it to adjust the torque setting for that retention ring so you aren't over tightening your bearing loads on the outer bearings.
2) I have no idea why you would need an impact wrench, I never used one once during the entire process.
3) You can manually repack the bearing by hand and they will be fine, as long as you really take your time and make absolutely sure you get grease everywhere inside them.
4)The snap rings are used to hold the differential oil seals in place along with the bearings if I remember correctly. I think there are two per axle for what you are doing.
5)Chopper is referring to swapping out the CV joint axle assemblies which rumor has it can be found for around $80 rebuilt each Here: http://www.alldiscountautoparts.com/...e=arc&s=1&my=1
6) If you don't have one, get a torque wrench or be able to rent one from an auto parts store. You definitely don't want stuff haunting you later because you misapplied a torque setting.
7) Read the procedure over in the manual a lot you are only going to get more confused, then more familiar. I printed out the sections I was using so I could have the at the ready for reference and so I didn't get axle grease, etc on my computer keys
You should be OK with the jackstand setup you have there. You may or may not need some cutoffs of wood to help distribute the weight more evenly when you jack on some places, and you want to make sure the back wheels are very securely blocked/chocked.

You do have to drop the axle, at least a little bit so you can maneuver the CV axles out. The bearings you are after are on them towards the insides. It is also a helluva lot easier to take the CV axles out with the differential brackets still on them. They will be just dangling and being held on by the oil seals and bearings. It is a tight fit getting them out. This is where you may have to have them pressed off. I have a light shop press at home. That's what I used.
Any more questions, let me know. I will try to get that walkthrough ready to send to you by tomorrow. I really don't have any pictures, but I can tell you exactly what sections of the manual to use and where you'll likely run into trouble spots.