The first is the best of the two pictures my husband took. Unfortunately, I had filled up memory, so that's all he could take. The second is a picture I took when I got back to my room at the hotel.
As far as how the guitar differs from a stock D-18 of any vintage, it's a limited edition made with Quilted Mahogany and Englemann spruce. As with any guitar of any vintage, each one is different, but I think I was very lucky with my D-18GL getting one that good guitar players rave about. It even sounds good when I simply run my fingers across the strings, and that's saying a lot. The top grain is very tight, often an indicator of good sound (it is, of course, an indicator of a very old tree). Dick Boak, at Martin, said that I was very lucky to get such a beautiful and good sounding guitar and this was when it was brand new. It has been played by Terry Clements (back in 2002), and David Mallett (in 2003). Both loved it. And, now it has been touched (but not played) by Gord himself.
The second picture illustrates another way my guitar differs from a stock D-18. Smile, please. Gord picked the spot; very clever don't you think? He specifically said, "I don't want to sign it on the top", and chose a spot where it wouldn't be rubbed out either when played or while in the case.
For more about the guitar, read the article at my web site:
http://gordonlightfoot.com/MartinD-18GL.shtml
and follow the link to the Sounding Board article at the Martin Guitar web site.