As you can see above, I've got three bathrooms with 1/2" galvanized pipe multi-turn toilet valves I'm wanting to replace with quarter turns. I originally was planning on just breaking loose the old valve but I've begun to worry a little bit about creating a leak on the other side of the drywall in the process. Is that reasonable?
So I moved on to the idea I'd use a pipe cutter (I would like the stub out shorter anyways) and rethread. But I guess that still leaves me with the potential of creating a leak. I don't mind taking my time and utilizing a pipe wrench to try and combat force on the other hidden end but do I need to just bite the bullet and cut an access and replace from the joint I'm sure is on the other side of the drywall?
Never done this type of work before and I know it's not an atypical or "hard" job, even my upstairs bath already had the multi-turn replaced but that was more than likely done by an experienced plumber. What's the SoP for this type of thing? By the way the escutcheon is pulled away from the wall a bit so it makes the pipe look shorter than it is.
Thanks for any help in advance!
EDIT: Sorry forgot to update. Couple weekends ago I hit it with PB Blaster and was able to work the old valve off while holding the nipple dead still. Got the new 1/4 turn on with some tape and putty and got the toilet back and mounted. Plenty of room in the back with the 1/4 turn now so glad I didn't bother shortening the nipple. Thanks again for the help everyone.