@sivat - you may be right about Sugino 75's switching to or being made available in ISO taper. I doubt that's true because I can't think of a reason why Sugino would do this, but it might be true.
So to the OP: this is worth checking on. But even if you can get the 75's in ISO taper, chances are the Campy BB you've got on your bike currently has the wrong size. I'd recommend you sell your Campy BB and crank together on eBay - will likely fetch a pretty penny.
on the asymmetry of Shimano (and Tange?) BB's, I don't know if there's a general database. I started a thread to try to catalog this, and the thread may be useful:
http://www.bikeforums.net/showthread.php?t=196235