Originally I was going to leave it at that, but I felt I would be deceiving you a little if I had done! You see, some of my XXV upgrades didn't quite work as planned.
The new battery pack arrived a good while before Domesday XXV came along, and I held it in reserve specifically so I could add it as part of the changes made for my 25th anniversary setup. Unfortunately, it seems that I must have stored it in somewhat humid conditions because I found that the CMOS RAM was still not being remembered whilst the machine was switched off. I tracked the problem down to some green corrosion which had got onto the contacts of the connector.
Taking off the connector housing and giving the contact points a good clean and then re-assembling it - that's the right way of doing it, sure, but that didn't happen! So the BeebMaster XXV Bodge was to chop it off and splice on the connector from the discarded battery pack. More red insulating tape, a bit of feature of July 2011 at BeebMaster Towers!