I've always thought they use standard AT power connector but I can se that they don't. I don't know how much this will help but looking at
this picture of Rev5.02 one can at least clearly see both GND, +12V and +5V being marked on the board. Now one could try to check what legs on the powerplug goes to those marked positions.
But now that you have a different rev you might not have these marks nor the positions of these on you're board but it might be worth a shot to look for markings. If not you could also try to use the know Zorro connector to find out the pinns of GND, +12V, -12V, +5V and -5V on the power connector from
this table.
