theparty had written this in response to
http://www.thestuccocompany.com/main...ox-401074-.htm
:
The OP returns:

All great replies. I posted the original question, so this is to let you
know that I returned and did read all the suggestions, and now I’ll be
able to tackle the job. Responding to your suggestions, in order, to let
you all know what I’ve taken from this:

I can’t get to the nail heads, but I will take my time. I’m sure the
opening will get larger, and there'll be no connections hidden in the
wall; they WILL be in the new box. I don’t think I’ll be able to dismantle
the old box, especially given the size of the nails in it now. I’ll try
prying the old box from the stud. I first considered leaving the old box
and patching it over, but the new box will be right behind it - no room
for two boxes opposite each other and no slack to move the wires far
enough. The old wires are knob mounted and the hot continues through the
box to a switch (in another box about 20 inches below this one) for the
hallway light, so I can’t easily abandon the wires. The attic light switch
is exactly at eye level - I gotta’ remove the box! A hack saw blade is the
answer; I’ll open up the hole a little, pry the box from the stud a bit,
then hack the nails and remove the box. If the wires won’t catch it I
might just drop it into the wall. The attic light is above the folding
stairs, and the pull chain should be easily reachable when I’m halfway up
them, the roof is low. So: I’ll look for a handle to hold a blade so I can
hack the nails off and if I can’t find a handle I’ll fashion one of duct
tape and stuff. Thanks!