Hi,
First things first, let's get something out of the way: a LARGE part of Kevin Shields' sound is the fact that he's using numerous double stacks of JCM800s and Jazzmasters/Jaguars. He holds the tremolo arm in such a way that when he strums it causes the bridge to move as well, creating that wavering modulation. Unless you have a similar setup, you aren't going to nail that portion of the sound.
That being said, you can get close. The algorithms on Space alone that will get you close are:
-Dynaverb: Kevin Shields used a reverse gate reverb, so see if you can't mess with size and threshold controls. That might get you somewhere in the ballpark.
-Manlgedverb: Configure the reverb to go as big (or small) as you want, and crank the drive as loud as you can.
-Blackhole: Set the decay time fairly short, and set the gravity to -100 (or somewhere else negative and large).
There are also two presets that come to mind that I think might be a good starting place: DoomDrive and DriveDoom. You might have some luck tweaking those.
Experiment with fuzz placement before and/or after Space, and hopefully those will get you where you want to go.
Nikhil
