Got brave today and tackled the plumbing head on.
Here's what I started with.
I wanted to have something semi-solid in the wall so I could hang things on it if needed, so I put a piece of leftover siding up. There are a couple of 2x4's on the other side that I attached the siding to, which will also be the attachment point for the water heater (see photo below).
After the siding came the actual wall covering.
Got all the pex going to the right places ... Well except the kitchen sink hot and cold. I inadvertently switched them so the hot comes through the wall on the right and the cold on the left, but that is easy enough to attach to the faucet correctly. I even wrote on the pex so I would remember that it is backwards.
So here is the whole kitchen side of the wall.
This is the photo I referred to above. The 2x4's supporting the siding on one side and the water heater on the bathroom side.
Plumbing for the shower, wall covering for the wet wall.