Nut Width?

The nut width of all of mine are 1.71"/.172". What's more important is the string spacing, E to e. That is a narrow 1.37"/1.38". I make new nuts with a wider 1.44" string spacing, making the guitar more playable.

The one thing I don't like about vintage Yamaha's is the very narrow 1.98" string spacing at the saddle, kind of narrow for fingerpicking. Much narrower than todays' 2.12" to 2.18". You can notch the saddle to spread them a little, maybe 2.06", but the only way to make it wider is to make a custom bridge with a wider string spacing. But I've found you can't go any wider than the width of the end of the fretboard which is 2.12".  2-3 months ago I started another project converting a width/thick neck 12 string FG-230 to a 6 string.  yamahavintagefg.boards.net/thread/168/1971-yamaha-230-conversion-yamaxl  This will include a very wide saddle string spacing of 2.25" or possibly 2.37", or possibly both.  Initially I'm going to leave the nut width the same (1.88") with a 1.57" string spacing. I got side tracked on a couple of customer jobs and another projects, but they will be finished in the next day or 2 and I'll be getting back to the YamaXL. 

Every vintage Yamaha I've seen had had the narrow 1.38" nut string spacing unless it's been replaced.