Originally Posted by MrBill_DIY
I am doing a minor makeover of a bathroom, and there's nothing wrong with my existing plumbing, but to match some of the new finishes in the room I need to replace the old chrome tub/shower trim parts with brushed nickel parts. The tub/shower faucet is a 25-year-old Moen single-lever faucet, which has a rather square-shaped backing plate that fits against the tile wall. I don't really want to mess with the plumbing, which works fine. It looks like you can buy a Moen backing plate that is circular. I wonder if I could get away with just removing the old square backing plate and replacing it with a new round one, without replacing the actual faucet parts.
Also, is it hard to replace the crosspiece in the tub drain? That's also gotta go.
Your best bet on figuring out if the trim plate is interchangeable is to call Moen. I believe their number is 1800buymoen. Moen even has several different styles of valves now, i'm not sure if all of the trim plates are even the same....
As far as replacing the 'crosspiece' that can bite ya in the butt too.....
Do you have a crawlspace? If you look from underneath the tub, the waste and overflow for the tub is just a 1 1/2" sanitary tee with a lower shoe for your drain, and an upper shoe for the overflow cover. There are a lot of different manufacturers of waste/overflow kits, there will be no guarantee that you will get the exact same trim to go on your existing kit. You may be better off if you have access underneath to just pull the entire thing off, get a new kit, and put it together identical to the one that is already there.
Thats what I would do anyway.