Delta R10000-UNWS Valve

I've installed this Delta valve in shower/tub. It comes with a square plastic piece called a plasterguard (#RP46075) that snaps into place. I assume it's purpose is to allow proper placement (depth) of valve in relation to the finished wall.

My question is whether this piece stays on the valve after tiling, or are you supposed to remove it before you install trim kit?

Normally, unless you're using the thin wall installation (i.e., say a fiberglass one-piece), there's no reason to keep the thing in place after you've got it positioned properly (well, it will help keep thinset, etc. out of the trim mounting holes, so you could leave it a bit longer). I HIGHLY recommend you temporarily install the trim and then get the valve set at a depth YOU like. If it's installed between the min/max marks, the trim will fit, but YOU may not like the way it looks. To the manufacturer, if it fits, it's okay, but that isn't necessarily what you want...mock it up first!

Damn....I shoulda asked the question BEFORE I soldered everything into place. Ah well, it still will look 1000% better than before I started the re-model. I can use this tip for the second bath project coming up. [It's kind of funny, this one of the times I actually read the directions and followed them before I started. Usually it's afterwards, when something goes wrong.....That sound you hear is me slapping my forehead]