Instrument Lights Not Working

At this point...I would think it is your circuit board. As you said..if your pins are fine when checked and you have 12 volts at your light "connector" pin "I" would say sorry, that I think you will have to pull it out again. Do a continuity check between your board light pin and follow the runs to all (+) bulbs. Also check the (-) side to ground. You may have a small open short in the run. I had this problem once and just got some gold circuit thread. I used finger nail polish to hold itin place. There's also a pencil of circuit board correction that will work.