My experience seems to be a bit different from most.
When I took my 120 apart there was significant corrosion almost everywhere
there was (or had been) felt between the body and the chassis. This was
especially true under the floor boards at the chassis cross member and on the top
surfaces of the rear chassis extensions.
It seems to me that even if the felt fibers don’t absorb water (and mine
did) the porous structure of the felt will and it will retain it in a lot of
places where you don’t want it. I’m using a closed cell foam tape in my