Been mentioned before, he had a few different Guilds. This one looks like an F50 Special with the Artist Award headstock, but don't believe it's an "R". Also looks pretty light, like maple, inside the soundhole on my 27" screen.
He also had one from a special run of 6 F50R Specials of which Bob Weir got at least one or 2 from '69 IIRC.
A quick check for pics of him shows all the "AA" specials with obvious braced dark rosewood b/s, so not really sure if he actually had a maple one as well. Probably just a lighting fluke.