The photos came thru this time.
Your right, the backing will need to be cut away.
Too bad you didn't post a photo of the back so we could see what your talking about.
Usually there is one or the other type of binding on the back. I have never seen where it has both.

If the mesh seems very well attached then carry on with the installation.
Word of caution, paper backed mosaics fall apart when cut on the wet saw. Maybe that's why they added the mesh.

Photo of the tile-back is here: Tile Back

The mesh is on pretty good. It's obviously glued on.

Do you really think it'll be easier to cut-out the mesh, rather than installing the tiles square and filling in the blanks with individual tiles (know what I mean?)?

Thanks again for all the advice.

It's up to you. A lot easier to cut out mesh and interlock the sheets than to cut out a bunch of separate pcs from another sheet and try to strip mesh and paper from those pcs so there's no lippage.

Well since I've never done this before and you have, I think I'll try it your way

Thanks again!

One new question:

My shower wall tiles are 7 3/4" x 11 3/4" ceramic. Can I use my 1/4x3/16" V notch trowel for this (which is the trowel I'm using for the kerdi).

Thanks!

No, you will need at least a 1/4x1/4 or a 1/4x3/8
Use the latter if the ceramic has a fairly pronounced lug pattern on the back. Over Kerdi I would also suggest you back butter the tile with the unmodified thinset.

Ok, here's (I think) a tough one then:

I built up a test-board to figure out the thickness of my finished wall. So, I took 1/2" drywall, thinset, kerdi, thinset, tile.

The thinset for the tile, as I mentioned above, was using the 1/4x3/16" V notch trowel. My test finish wall ended up approx 7/8" thick.

If I switch to the 1/4x3/8" (square notch?), how much do you think that will affect the finish-wall thickness?

Thanks again.

Why does it matter when its on a wall?
If you got 80% coverage with the v notch trowel, then use it.

Two of my shower fixtures have to be installed "just-right" and don't have cover-plates or anything to make install easy.

Both will be attached using brass-nipples, and I want to make sure I get the right length the first time.

So, I made a test board (described above) that I'll use to judge how far the plumbing will protrude before I put up the finish wall, but that was done with the other trowel.

I assume with the 1/4x3/8" trowel, the tile will sit a little higher, but I wonder if you have a guess how much?

I'll still use my existing test board when doing the plumbing, but I'll adjust for the expected extra thickness. I'd assume it would be something small like 1/16", but that might push me up a size for the nipple.

It's very rare that a stock nipple will be just right. I make custom brass nipples for all my jobs that have body sprays etc.
They are easy to do if you have the right materials.

Most plumbing fixtures that have nipple attachments with escutcheon covers usually have an adjustment range up to 3/8" or more. Same with the main valve trims.

You should try and post some photos. Thats always helpful.