How is the foreend of a lever action carbine and its foreend tip bedded or otherwise adjusted to make the carbine more accurate, plus improve the maintenance of sights' "zero" despite significant changes in humidity?

Does this procedure improve most lever action carbines, for example Winchester 1886, 1892, and 1894 carbines?

There was an article in a long ago 'Gun Digest' that covered just what you asked. As I recall the two important factors were the bedding of the forend and magazine tube and the tube in the barrel bands. No contact with the tube and forend and a slip fit with the end band (Mod. 94). I did this to my 2 94's and they both shoot great. I will do some digging and see if I can find the year for the Digest.
C.G.B.

Too many parts hanging off the barrel; best you can do is make sure everything is tight. That is all the GD article accomplished. They are what they are. The sights are the limitations, not those other things as long as they are tight. No matter how you treat them, they are still attached to the barrel. (I'm not sure it matters, and I have had at least 25 lever actions.)

ML MCPHERSON - ACCURIZING THE FACTORY RIFLE

This a a good book that includes sections on two piece stocks and single shot rifles with lots of tips for tinkering along with a lot of bolt action rifle.