One thing to consider about some David Gilmour/Pink Floyd guitar parts is, not all of them were played on a regular guitar, but either a lap steel or pedal steel guitar. When I bought the DVD of Making Of Dark Side Of The Moon, I finally realized why there's a lot of Gilmour parts that I can't replicate on my regular 6-string guitars.
One of my favorites to play, on guitar, is "Set The Controls For The Heart Of The Sun" (from A Saucerful Of Secrets), while on bass I like to play "Money," "In The Flesh" ann "Another Brick In The Wall Part 2." I'm a bit on the "sacreligious" side, though, when it comes to playing "Another Brick In The Wall Part 2," as I don't use drop D tuning for it.
Matt