Wow! Large Number!

Logic Level 4

$\large\begin{array}{llllllll}&&&&A&B&C&D\\\times&&&&D&C&B&A\\\hline&5&C&C&B&A&A&D\end{array}$

What is the value of $\overline{DCBA}-\overline{ABCD}$ ?

Clarification: $A,B,C$ and $D$ are distinct single digits with $A$ and $D$ non-zero.

Excel in math and science