Small marks near the centre of a record can be difficult to read and easy to overinterpret. If you are documenting your own copy, begin with the characters you can see before trying to identify a pressing from them.
Handle the record according to appropriate care guidance and use ordinary viewing angles rather than rubbing, tracing or applying substances to the surface. If a mark remains unclear, leave it unresolved.
Record each side separately. Keep spaces, symbols and uncertain characters visible in the transcription; use a note such as “possibly B” rather than silently selecting the character that matches an online listing.
Compare the whole copy
A matching fragment is a research lead, not conclusive identification. Compare the label, catalogue number, packaging and any documented variant information as well. State which source supplies an interpretation of the inscription.
An invented catalogue note might read: “Side A includes the letters XY; final character unreadable.” That is less impressive than a confident pressing claim but more useful to someone examining the copy later.
Keep observation and interpretation in different fields. If new evidence changes the identification, you can revise the interpretation while preserving the original transcription. The record has not changed merely because your explanation of a tiny mark has improved.
Editorial illustration from this site’s image library; not documentary evidence of the example or object discussed.