Registration for ISMNs?

[Peter M. Armstrong]

I have 37 musical works (most for solo piano) installed at
IMSLP with "Edition Ottaviano Petrucci" as their publisher.
However, not one of the scores has an ISMN.

Only belatedly realizing that ISMNs might be a good idea,
and accessing the U.S. ISMN Agency's website to register,
I see two applicable options:

"Register With An Existing Publisher":
I cannot do that, as neither "Edition Ottaviano Petrucci"
nor "IMSLP" appears in the list of Existing Publishers.

"Register a New Publisher":
So I'm writing this post to ask: Could IMSLP register as
Publisher, so that I can then register myself as above?

I presume that, once these registrations are complete and
I've ordered and received ISMNs from the Agency, my task
will be to edit those numbers into the score originals on
my home system and re-upload the results to IMSLP.
Is this correct?

I'd appreciate any comment!
Thanks in advance,
Peter M. Armstrong

[kosboot]

I think this is related. About 2 years ago on Wikipedia I asked whether they could make live links to ISMN as they do with ISBNs. An administrator explained that, unlike ISBN which have a registered web presence, ISMN does not, so until they do, one can not create live links.