[Arran]

 One thing I should add about my capacitor re-stuffing method, the type of corrugated cardboard I have been using is a thinner type, with two layers, I think it used to be a box for an ornament of some kind. It tends to bend easier then the type you would run into for something like a moving box, and if it ends up being too think you can peel away the layers. As I mentioned I cut the cardboard into strips, like maybe 1'' wide, usually a little wider then the body of the capacitor is long. Then I tack one end down with hot glue to the cap body where the cap body is roughly in the center of the strip, then I warp the strip around the body of the cap, cut it to length, then tack that down too if needed. Then you take the whole affair and stuff it into the old cardboard tube until it's centered between the ends, if it won't go in peel a layer off the cardboard and try again.
 Then you take the glue gun and start injecting glue into one end, a little at a time, till it's filled. But one thing you need to do is wait until one side cools and hardens before you fill the other side, so you need some way of holding it up on end until it does, so normally I restuff three or more tubes at a time so the first is cooled by the time I've finished with the third or forth. If I'm in a hurry, or the cap is of a large diameter like a toilet paper roll electrolytic, I will put it in the freezer.
 This is something that isn't all that hard to do, it just takes some practice and experience to refine. For example I prefer to melt out paper caps in a toaster oven set to 250 centigrade, a heat gun works but you can scorch the paper labels if you are not careful. Believe it or not I have a small stockpile of paper capacitor tubes that I cleaned out in advance just for future projects, usually along with ones belonging to whatever set I am restoring, since the toaster oven was already hot.
  One thing that I have been trying to find though is a source of cardboard or paper tubes of the right diameter and wall thickness to use as a substitute for the originals, like for sets where many or all of the originals are gone. I thought maybe the kind they use for firecrackers might work but  I think that the walls are too thick.
Regards
Arran