Please note: the SEMA damper standard (S.F.I. 18.1) does not rate a damper’s effectiveness, or certify that it works at all (let alone on a specific engine) - only that it didn’t explode during the test. Their interest is limited to safety and qualify control, not specific engineering results.
I couldn't even find a requirement as to how accurately it must fit the subject crank nose. If it goes on easily it won't work, but will fret the snout and damper ID.

One way to tell if it's working: it's hot after a run.