Sounds like Q420 might be shorted. These are linear supplies, so they don't mind being brought up slowly on a variac, if you have one. B+ should follow the input up to about 14V and stop. If it keeps rising, you can shut down before burning stuff up.
Also are you sure you replaced C432 with a good 100uf200v capacitor? When this is bad, power supply runs high and sometimes causes this resistor to burn.
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