I think it is almost impossible to requeen a nuc (or hive) with the existing
queen in place.  One must find and remove her...or kill her.

On the other hand, if one starts with a queenless nuc or package it is easy
to introduce a new queen.  Remove the cork from the candy end of the cage,
put a hole in the candy with a long nail.  (Don't injure the queen doing
this.)  Put the cage candy end up in between two frames.  In 72 hours check
and remove the cage.  If the queen is still there, lift the wire and let her
go on top of the frames.

You do not need to remove any workers from the queen cage.

Best of luck,

Lloyd
Lloyd Spear, Owner of Ross Rounds, manufacturer of comb honey equipment
for beekeepers and Sundance pollen traps.
http://www.rossrounds.com
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