Some further internal checks for modifications compared to the original Agilent meter.
Agilent PCB is a REV 4.
New Keysight is a REV 6 with the mods shown in the attached pics. otherwise it appears to be the same.
Noted that the input divider and fuse holder clips have been soldered in after the main PCB had been loaded and soldered on the REV 6 , but were done at the same time as the whole PCB on the REV 4 (or at least the REV 4 had a better clean!).
On my REV 6 the noted parts changed (or appeared to have been) are BD4, BD5, C53 and R55 which was not as obvious as a hand solder and lastly, as Zbig asked, on the top side BD7 has been changed to the same value as R55.
Sorry for the pics , had only phone camera , but they still convey the required info.
EDIT: I just removed C53 from each PCB and tested on a fluke 87V capacitance mode and both measure 3.3uF, so no need to bother with this component.
Question as to why the later REV PCB looks like it was hand soldered
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