HEX to ASCII
The modified contra code is seen here in hexadecimal on the left and its (almost) ASCII representation on the right. You can see the ending screen text and the credits. That file is loaded and ready to be flashed to the EPROM chip that is loaded (you can see it in the 'Device Location' section on the right). A new NES cartridge is just 28 solder points away!
this cart rebuild is pretty easy to do, in fact... more people should play around with this stuff IMO, and you could even make a little business selling custom or hard-to-find carts to your friends, or at conventions. all the ROM dumps are already online.