Tub Spout difficult to remove
I have a squealing shower diverter - in the tub spout. This is an American Standard faucet/spout.
I would like to simply replace the tub spout to try a new diverter. I am having difficulty getting the existing spout off. There is no set screw underneath, so I assume the spout can be removed by literally unscrewing. An attempt by hand got me no where - so I began trying with large pipe wrench and/or large adjustable pliers. However - I'm afraid of doing some damage to the copper fitting/pipe behind - this puppy does not seem to want to budge!
So 1) I assume this is a screw-on since there is no set screw. 2) Is there such a thing as a slip-on without a set screw? Either way - I almost don't care so much if I need to destroy the existing unit to get it off - it's mostly that I don't want to disturb the copper pipe/fitting through the wall by turning what seems to be way too hard.
I don't want to give up on this because it seems like such a simple replacement - any advise greatly appreciated!
PS - at Home Depot the folks pretty much insisted that all tub spouts are "plastic metal" - that is - they are plastic. Is this true? My existing spout (assume American Standard) seems to dent, like metal (from trying to twist off).
Thanks much -