Recapping didn't fix the problem, neither did replacing the HOT or flyback. Likely, these parts were all still good, unfortunately. I should have known that the issue was with the SMPS, because even with the old components, the power led would flash on and off rapidly, and a very, very faint ticking could be heard if I were to work on it in an extremely quiet room. I began checking the DC lines and eventually found that D805 was shorted. Replacing it with an identical fast recovery diode of required rating brought it back to life. HV immediately appeared, and I adjusted the B+ trim pot, now have a solid 86V B+. Just a few tweaks to focus and screen controls were all that were needed. The monitor lives again after nearly 6 years of being dead.