Hallo Milk,
sorry to say that it's not Simon here ;-)
My name is Marco and I'm fm Italy; I happen to know a few info concerning Simon's past gear since at the time I lived in London and I had chances to meet Simon and chat with him about basses and gear..... That's how I know about it; I wish I had a more interesting truth to share, but this is how it went.
Another thing I remember is that Simon told me he used two different StingRays for the Disintegration sessions; an all maple neck one with black body and white pickguard with a standard tuning, and another one, black and maple neck as well, with a black pickguard tuned D A D G.....
So, when you hear low D it is the black/black, otherwise it is the black/white one.
During the tour he used mainly his Washburn AB40, switching to the B/B StingRay when low D was needed.
since he did not like the lows that came out of the AB40, he changed the setting on the Boss GE-7..... Everything flat except the two lowest slides "full throttle"
Hope it helps
Marco