Here is what I did to gain Yaki rep, no scripts involved:
(1) Put a Adv Nav Sat in Oracoke's Storm, and also in all Paranid sectors with a Millitary Outpost (Empire Edge, Preacher Refuge, Pontifex Seclusion)
(2) Keep an eye on Paranid Millitary outposts , looking for owned ships heading for Yaki sectors. Assign an M5 to follow the ships, and once they get into Oracoke's Storm, kill the ships. You would gain about 2K+ rep for 6-8 ship kills. The loss in Paranid rep is small (about 5-10%, assuming you are already high with the Paranid).
(3) Jump your ship into Oracoke's Storm. For each jump, there is a chance that a group of commonwealth freighters is spawned. Keep jumping from one gate to another until a convoy of freighters are spawned. Putting a NavSat in this sector also helps. Kill the convoy to earn yaki rep. you earn about 20 rep point per kill. This is also a good way to acquire freighters for your Hub mission
(0) How to check your Yaki Rep: (This is what Gazz wrote above, with step-by-step details).
0.1 Save the game.
0.2 Turn on the Script Editor (Thereshallbewings)
0.3 Turn on Debugging (the 2nd debug option once the Script Editor is run)
0.4 Target a Yaki ship and read the rep against you
0.5 Restore the save game. (If you want to stay vanilla)
(for me)! 
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