HP 3458A A2 Board Revision E Changes and Issues

[tonyz663]

I am currently working on an issue with my 3458A A2 board (Rev A).  I have the CLIP and it has up to Rev D in changes, which I already incorporated.  I noticed that there was a component added in series with 100 ohm resistor R006 (appears to be a diode with number 1902-0956?) from reviewing photos of Rev E boards.  Does anyone have a Rev E or later schematic diagram for the A2 board to confirm any changes?  Let me know your thoughts.

My current problem with the A2 board revolves around the SCAL 1 and 0.1 calibration functions.  I was recording voltages at both frequencies and get a steady ac voltage reading from the 3458A at 100 kHz and get a slow voltage decrement at 8 MHz for both 1V and 0.1V rms.  The 3V rms voltages seem to be consistent and no drift downs with frequency changes.  I am using a 3325A that was calibrated around 2016 and does not drift down with other meters.  Are there any thoughts on areas to check from past experiences?