[Evans, Marv]

If the galvanized pipe is in such bad condition structurally, I'd be really hesitant to go torqueing around on it either from the outside of inside. Those internal pipe wrenches will stress the pipe just as much as a regular pipe wrench. If it were me, I might look into some kind of compression fitting to use over the galvanized nipple, assuming it isn't destroyed right up to the 90 degree ell. If your friend is going to try to get another ten years out of it, any stressing on that old stuff might just reduce how long it lasts.