you can figure out your leads using an ohm meter. Measure ohms between all of the wires and record the results. You should have 2 sets of 3 wires that have continuity. These sets are your two phases.
Within the each phase 2 of the wires will measure twice the resistance between them as the third will beween the other two. The wire that measures half the resistance is your center tap.
here is a web page to help explain:
I would connect the two wires with the most resistance between them to A and /A on the Gecko, then connect the two wires with the most resistance form the other set of three, to B and /B. Make sure to cap the centertaps separately.
This should get you going. If you need more preformance you might try wiring half coil.