I tried to restore 2 old R55s with 50% success (ruined one and got the other one to work like new).
Here is the algorithm I developed:
Step 1: taking the generator apart.
-unscrew the tip (easy!)
-make sure the inside of the tube is wet (packing may contain asbestos)
-unscrew the tip cleaner lever and pull it out (Not so easy, some heat to soften graphite packing should help, don't force it out too vigorously or you can break the excenter - this is how I killed the second R55)
- take a sewing needle or some other similar object and use it to gently push the cleaning rod from the tip side. It should fall out from the other end together with a brass mesh screen.
Step 2: cleaning the generator tube.
Older R55s contain some wool-like stuff that can be asbestos, so I used a little brush to clean it out in a glass of vinegar (the tube was submerged in vinegar all the time). The packing was wet all the time, so there was no hazardous dust.
When I dissected another R55 that I destroyed trying to take apart, I found that the tube is also lined with some paper-like material on the inside (1-2 layers). It was evenly brown, looked strange and when I tried to light a tiny piece of it, it turned very light grey (asbestos paper???).
So I took my another R55 tube to work and submerged it into 50% sulfuric acid to destroy the rest of packing and gunk. The solution in the test tube turned brown and there was quite a stink of rotten eggs coming from it (hydrogen sulfide). Apparently there were a lot of sulfur compounds in the gunk, which is interesting. After that I washed the tube in water.
Step 3: repacking and reassembly.
-packing:
I used glass fibers to pack the the R55 tube. You need just right amount of fibers to be able to insert the cleaning rod back into the tube without bending the needle. I can't tell exactly what is the optimal amount of packing, so be careful if you decide to try.
-Insert the cleaning rod:
There is a cylinder with a hole in it's side on the base of the rod. Make sure this hole is facing the cleaner lever because this is where this lever will be attached.
-Re-install the cleaning lever:
If graphite packing is still good, it can be reused, if not - teflon tape worked perfectly for me. When putting back the cleaning lever, make sure that excenter clicks into the hole in the base of the cleaning rod. This should not be hard to do.
-Clean the brass mesh screen and gently push it into the tube with a match.
-Put the tip back. I had to replace the enlarged old tip with a newer V tip.
Put the gen into the lamp, test it for leaks in a bucket of water and it's ready to vaporize fuel again! 
Mine is now working in a Quick-lite table lamp.
