Mark51 (good name for a Guild classical)
Pleased to make your acquaintance. Soon you'll be wondering if you're pleased to make mine.
I don't have a 170 (although I'd like to get a 160, 170, or 180 in one of those weird colors a few had--Canadian pink, Upsher purple, etc.).
I don't know, but I would guess the bridge and nut were made for a wound third. I put a wound third on anything that's not a solidbody. Even my bicycle. On all of my starchtops, I use a set of tens. It's easy for me to remember because it rhymes with "Depends." But I don't know of any tens that come with a wound third, so I use separate 18 gauge wound strings from juststrings.com. "Eighteen" is easy for me to remember because it's the cut-off age for all of my groupies.
You might try flatwounds. I like them, and I don't care what normal people say. But I do care what Coastie says, and he improved "Hattenhauer" by changing it to "Hatted Frau" and POW! it's Hatted Frau now.