Place the doll, er... action figure, about where you're going to want him on top of your top piece. We're getting ready to cut the shape that Han will be framed by. Measure twice and cut once the square shape around him. This would be a perfect time for the scroll saw or some quality Dremel time. Be sure to check out the second picture below to see what I mean.
You don't need a fancy saw, you can use the same saw from earlier. Just glue all the pieces back together when you're done and you're good to go.