I have been using rubber cement to attach labels to piano rolls with
excellent results.  It is flexible, acid free and reversible.

If the label has previously applied stiff adhesive, flex it by pulling
it across a straight edge such as your table.  This will pre-form the
label and break up the adhesive.  Then apply a liberal amount of rubber
cement to the label and attach it to the roll while it is still wet.

Position the label and smooth it with your fingers, squeezing the
excess out.  When the cement is dry, rub the excess that is visible
with your fingers and it will magically come off, along with any dirt
that may have been on your fingers when you applied it.

Jack Breen
Southborough, Massachusetts