Foehammer assuming you go brushless outrunner which means no gearbox and a direct drive, which is what I plan on doing, you'd have to use an outrunner motor mount and E Flite has what you need for maybe another $10. The motor then connects to the ESC you'd need to buy as mentioned above and then that into the new receiver. You can't use stock PZ HZ radio gear with brushless set ups. Though someone has come up with a board that will allow you to use the stock gear. It's around $30. On the RC Groups Boards I'll see if I can get the thread....but personally I'd switch out all the stock gear. Put in decent micro servos such as the Hitec 55s or the HS 81s and a good micro receiver. If you don't already have a 72 mhz aircraft radio you will need one of those as well as the coresponding crystal number for your reciever.

As I mentioned, you could easily use the stock battery on an upgraded radio set up. But if you choose to go lipo you'll need to make sure that the pack will fit the battery cage. If you don't have to cut out space to accommodate a new battery all the better so why not go with the stock one....it's really a question of choice, how long you want your flights to last and how much more you are willing to spend and how much tinkering you want to tackle. I find 10 - 15 minutes plenty of time for flights. After that my concentration goes..

Do your research and try the plane stock for a while before diving into Mods and upgrades. Good luck. [8D]