Stadium Power Supply Help

[BigWick]

I'm working on a stack of Stadium DEL944 (Rev a.) power supplies from some VLT cabinets and I'm seeing a consistent issue of one or both of the 24v MOSFETS short and on occasion you also nuke the MOV thermistor or a rectifier diode further downstream. Replacing them all 75% of the time beings the PSU back up. The rest of the time you get twitching from the PSU fan but it's stuck in a shutdown loop like something else is bad. I've swapped the MOSFET/PWM control board between good and bad systems with no change. I also swapped the connector distribution and 5V/3.3v DC-DC boards. Still no power-up. The fault is almost certainly on the main board of the power supply but I cannot find a schematic.
Does anyone else know of this issue or know where I can find a schematic?

[BigWick]

Okay I have now gone through two supplies to triple-check I didn't miss something. One with the fault above and one working and swapped every soldered-in riser board in an attempt to isolate which board(s) it could be.

-Swapped the main heatsink and it's components (bridge rectifier, PFC and MOSFET's) - no change
-Swapped the PWM/PFC control board - no change
-Swapped the secondary rectifier heatsink assemblies (both of them) - no change
-Swapped the DC-DC regulation module - no change
-Swapped the output distribution board - no change

The fault is on the main PCB. On a good PSU the two bulk primary DC filter capacitors charge up to a little over 400v but on the bad board they will peak at 260v DC. Power to the PFC/PWM board is also unstable. The PFC feedback winding on the main choke is not open. It's something early on in the DC boost but I cannot find a bad diode or resistor both visually or with the DMM.