I recently bought a 1982 or 1983 Guerciotti. I rebuilt it to my liking, and now I'm wondering about the chain stay. It is chrome, and is a little pitted and peeling. Can I put on a clear chainstay protector without doing more harm? Any other thoughts about protecting the chrome?

Anything is better than bear chrome. The clear should do ok. I use black electrical tape. Not because it is great, but that is because I have a roll of it. So it is easily available. The black tape covers up the existing nicks, takes much of the impact of the chain, but probably not all of it, and is easily and inexpensively replaceable. I ovalize the corners the best that I can to make it look like it not just a piece of electrical tape. Electrical tape is available in colors as well, so long as you don't mind primary colors or white.

Clear chainstay protectors are a cheap, effective and good-looking solution. My only concern would be that removing the protector might lift up more chrome, if it's already flaking off.

You can go cheap and also use electrical tape as noted above, or even clear packing tape, if you still want to see the chrome.

...the simplest solution is to simply remove the wheel and chain, drive side crank, and anything else you can't mask off, like the rear derailleur and cabling, mask it at the BB and the dropout, and paint the whole stay to match the color of the bicycle. I've done this on a number of Italian bike frames with bad chrome. Many of the Italian makers were not real fastidious in their chroming. The paint will be more durable if you do a final urethane 2 part clear coat.

If you have trouble matching the color, you might need to mask off the main triangle, pull the rear brake and saddle/seat post, and paint the whole rear triangle on both sides, to get something that looks pretty respectable. I like chrome just as much as the next guy, but once it starts to go, it looks like hell. I've never been a fan of the aluminum foil trick, although it probably works for a while.

What's a bit ironic is, the chroming process that's done to frames, supposedly to keep them from rusting because of chrome's hard finish, actually can be the cause of rusting if the frame wasn't properly cleaned of chemicals used during chroming...... The frame actually will be rusting from inside out and you'll discover the problem when its too late and pinholes and perforations on the frame tube start to occur.....