I have two fo inlines sitting side by side.  I'd like to mash these
two characters up, or super-impose them.  I would like to create a
checked checkbox from the two ZapfDingbats characters, ❏ (the
box) and &#x2713 (the check).  This is flowing text in a paragraph,
and I need to [ ] X move the X over the [ ].

Is this possible?  I can achieve the desired result with absolutely
positioned block-containers, but this is not an option, since the text
is flowing and the checked box has to part of the flowing text.

Thanks,
Karl..