Perhaps someone could explain why the UD Tech board's PCI slots are facing in opposite directions?
They're not.
One is for 5v cards, and the other is for 3.3v cards. I'd assume the PCI-66 slot is the 3.3v one.
PCI cards either have a key in the front for 5v, a key in the back for 3.3v or both for a universal card.