I checked one of my 453s that is above 20,000. The TP voltages in the schematic are right. Check the transistors and diodes in that area. The 3,3mfd condenser could be bad. I have had ones with high ESR I replaced with Nichicon ULD type. R473, R674 and R483 I raised to 1 and 2W respectively. Yours could be high in resistance. The originals are 1/2W carbons. The tunnel diode will be good if you can get a signal to trigger.
The trace problems you describe sound like the astig and geometry(?) need adjusting.
Mark
