Another YouTube channel I just found. Test gear tear downs. Very very good ones
https://youtube.com/user/alfa49alfa
Looks familiar, the same channel as the Agilent 54621A scope video, mentioning the connector damage, caused by a forced on older module on the back. Got the HP 803A VHF Bridge showing in the other videos, a few days ago, but not had a chance to watch any more yet.
Edit: not sure about this channel, quick glance at the 8690B video, seemed to be parting it out, for the HV caps & transformer.
Edit 2: watched part 1 & part way through part 2, he scrapped it, can't understand why, as it was working and in excellent condition, unlike the stuff that appears over here.
David