The 145 sounds low. It should be closer to 160v. The 19" chassis can accept either a STR3123 or a STR30123. The schematics will detail the different jumpers necessary for each VR.
Diodes should always be pulled, at least one leg, in order to test them.
You can also try disconnecting the degaussing coil in order to remove it from the equation.
Pull the fuse and test it for resistance. It should read as a short but I have seen the fuses partially blow creating high resistance. While you have it removed make sure the two fuse holders are snug. If they do not have a strong grip on the fuse they can create a high resistance area as well.
Resistors R101 and R103 - make sure they are not loose. with the board upside down wiggle each resistor while watching the solder points. Any movement needs to be fixed. They can look like the solder is still good when it has actually broken loose from the solder pad.