all the missing wills are I think summarised on MNB (there may be a few c 1720 I havn't completed but think I caught all the later mid 18C ones - I looked at the originals - in all cases a complete book was missed - there are missing individual entries from the index esp from episcopal films) - the Manx Museum is in process of digitising the wills but suspect will be some time before done.
The catch with the episcopal wills is that they are not numbered (nor are 99% of Archideaconal pre 1700) but identifying them by position on a film is not clever as the order may not be preserved (not all are bound into volumes) thus a later refiming implies a new indexing - the binding is a significant nuisance in that loss of page margin on film makes some names unreadable but as you get back into 17th century damp and longtails have made a number unreadable