aqueous fixatives will remove the fluorchrome label, (water soluable)
and any decal will definately remove your label.  i fix in cold (4
degrees C) alcohol and process and embedd in glycol methacrylate to
preserve fluorchrome label.  there was a recent article in JOH about 10%
NBF and the preservation of fluorchrome label, but I think it was for
very thick samples (whole heads of femur), perhaps the aqueous fixative
had not gotten to the thick area in the center of the bone,  in my
experience biopsies fixed for more than 24 hours in aqueous fixtives
lose fluorchrome label.  if the alcohol is pre-cooled the morphology of
the sample is well maintained.  this is my experience, i am sure others
will disagree.
patsy ruegg