We discovered over Christmas break that the guest shower had issues.  Once the company was gone, it was time to tackle the repair.  First step is to gather the tools, then remove the fixtures.  It’s nice to have a husband who is confident in his plumbing abilities, yet I was still stressed over the whole thing.  I wasn’t expecting it to turn into such a major project, nor to have the water turned off for most of the day!

All we really needed was a new cartridge to replace the worn out one; however, the fixture itself was pretty old and spotted, and the individual parts were more expensive than a new faucet, so we bought a new one. Once we got the box home, though, and opened it, we discovered the the cartridge was already installed in the pipe fitting, and no way we were going to replace the whole thing inside the wall.  So, back to the store we went (but after taking time for a picnic lunch.)
The wonderful employee at Ace Hardware told us about this apparently amazing product to get rid of the water spots on the old faucet and handle.
It worked!  So Wayne installed the replacement cartridge and put everything back together with the old fixtures.
Now we’re ready for guests again.  And this time when you shower you can have hot water AND decent water pressure at the same time! 
For future reference, our faucet is a Moen, model Chateau L2353. It takes a 1222 or 1222B cartridge. I learned that the “B” stands for “bulk” and they’re interchangeable.