I used a combination of methods. I started with sand blasting and then moved to a wire wheel on a 4" angle grinder and chemical paint stripper and putty knife.
Some points to ponder:
If you leave the transmission in place, be sure to plug the filler holes well before you sandblast. Sand gets everywhere. You'll be cleaning it up over and over even when you think you've cleaned the last of it.
Chemical strippers leave residue that will need to be thoroughly cleaned off after you've removed the paint.
Get ready to contort yourself in many different ways. The better contortionist you are, the better job you will do.
This isn't expert advice, it's just what I did to clean and paint the inside of my car and it looks much better.
A lot depends on condition and extent to which you are stripping. If you are doing the entire body or entire compoinents like a deck or door, then either media blasting or tank dip (where possible) is your best bet. If you do tank dip, try to find a place that can also e-coat it afterward.
Soda blasting is great for removing paint without damaging other parts. It is not so great at removing rust.
Sand can warp and tear up metal, usually plastic bead or glass bead is better. Make sure you are wearing a quality respirator, rated for sand blasting. Silicosis is something you don't want to deal with.
Brush-on stripper makes a huge mess but some folks like it.
For body panels, while it takes time, don't underestimate a good DA sander.
If you are doing smaller components get yourself a blast cabinet. You do need a hefty compressor to keep up with any sort of blasting but I consider my blast cabinet and my garage lift to be among the best tool purchases I have ever made. Just make sure you get a good one, not a cheap Harbor Freight unit.
Saw on one of the Porsche forums that there is a place down in Jackson MS, that also does stripping and resotoration. They have a Pyrolytic Cleaning Oven, phosphoric Cathode Dip tank, and they have a deal with the Nissan factory to allow cars to be e-coated in the Nissan E-coat vat.
If you are just cleaning everything off the body, the oven is the way to go. If you are going to be fixing rust and e-coating the whole process is the way to go. You could even put the chassis back in the oven after dipping to burn off any residue that might later cause a problem.