Since he had to be recognizable from ages 8 to about 48, I gave him a distinct haircut and very recognizable facial features.
I tried to make the scan large enough so that you can see the notes and corrections. I haven't been able to find any copies of the pencils but if they turn up later I'll be sure to post them as well.
I remember struggling with the layout on that last panel. It wasn't an easy action for me to work out but I think it gets the idea across. On the other hand, if I had it to do over, I might not show Jack smiling as he delivers the line. His standard scowl probably would have worked better.