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Sorry it's been a few days since my last reply, here is what I have found:

I did desolder and check the bridge rectifier, and it was good.

Voltages according to diagram:

Where voltage should be 3.3, it's 7.6mV, at the capacitor C4419 and at Q4102
op amp leg 5, instead of 0V, it's 8.34V
op amp leg 7, instead of 2.4, it's 0.93V
Q4102 emitter, instead of 1.0V, it's 0.49V at the base, and 0 at the emmiter and collector
R4312 does read near +55, at 54.8V

Replacing the op amp U4206B made no difference in any of the readings.

Q4105 and Q4106: both are 2N2222 NPN transistors, both had hfe within spec, 122 and 189. Replaced them anyway since I had some and they just slide in and out of their sockets, and of course no change.

C4419: ESR of new capacitor measured 0.03, and neither of my meters could read it's capacitance, so my meters probably just can't read capacitance that high. So the original Sprague may have been OK, BUT after putting the new capacitor in, the -8V test point now reads, 0.75 Volts, and that was the only part I had changed out at the time. I checked continuity between C4419 and all the other parts it connects to in the diagram, R4311, R4204, and C4203 on the negative side, and Q4102 on the positive side.

Voltages at the test points are as follows:
+110: 110.9
+5: 4.96
+55: 54.8
+15: 14.95
-8: 0.75 after replacing capacitor.

Replacing the op amp and Q4105 and Q4106 made no difference.

SO this seems to leave Q4102. It's a Motorola 852, with 034900 below the 852 number. Looking at the labeled face, it's emitter, collector, base, and is screwed into the heatsink. I can't seem to find a datasheet for it, anyone know what the modern equivlent would be?

Thank you for all the input so far