Hi Mary & Rick,
I have heard back from a contact at the Museum (MNH) library, who tells me that the deposit call number is MS 10180, and is called "The papers of Mrs Constance Radcliffe MBE BA". There are two regular archival boxes, and two boxes of card indexes written by CR with this deposit. She says that the boxes include plentiful genealogical charts as well as other papers. Also, prior to her death, CR was in the habit of passing in various papers now and again so potentially there would be other deposits of interest as well.
Mary, I hope this saves you some time tomorrow. Knowing the call number means that the boxes will be easily found.
Good luck as well with the will, with the name of the croft.
Sue