A useful tip that may save you a lot of headaches.

Have (1,0,9,1,5,6) represent the number 651901. That means that $number[$i] is the 10**$i constant and makes lining things up much easier. You'll need to throw in random reverses, but it makes everything else make more sense.

When you're done you may wish to read the code to my (semi-joke) module Math::Fleximal which does something very much like this. (But not necessarily in base 10. Though it can work in base 10.)