We have a scanned copy of the index for this file which you can download and then look up to work out which letters interest you. The "Names Index" on the index file which you can download below starts on page 13 (also page 13 of the pdf file).
The first letter starts at frame 3. There are no page no.s and no letter no.s so the authors have used an indexing system to help you find the letters. Refer to pages 3 & 4 pf the index download.