(defun C:CHDIMTXT ()
  (setq dimensiontext (entlast))
  (setq entitydata (entget dimensiontext))
  (setq entitydata
    (subst (cons 8 "DIMTEXT")
      (assoc 8 entitydata) entitydata
    ); end subst
  )
  (entmod entitydata)
  (princ)
); end chdimtxt