Try grounding/5Ving the gates of the transistors and the outputs of U6?

In the same way that grounding j113-6 tests if all the circuitry from the coil up to the connector works (because you simulate what the tip102 does, ie grounding the coil), you can also manually trigger other parts of the path. For instance, if you find where u6 connects to q36 and touch a wire carefully there, and the coil fires, you know that both your transistors, and the assorted circuitry, is good. If it doesn't fire, you try triggering in between q36 and q42, and if then it fires, you know something about q36 is bad. etc etc

Just saw this. Did you fix it yet? If not, record all the voltages around the components you mentioned (Q42, Q36) and the voltages on the equivalent circuit for a working jet, and post the info here. zacaj's advice was also good - did you try it?