first hook up his samsung drive and backup his firmware, then load into windows and make your iXtreme 1.4 firmware and open it up in firmware toolbox4.6, then get your key from your hitachi 47 and replace the key in the iXtreme1.4 firmware with yours. now spoof the firmware using toolbox to 47 hitachi drive. now make sure you havent done anything to your friends backup you made cause you dont want to lose his key! Now boot into your usb flash drive in dos and flash the drive with the modified firmware you prepared with your key and spoof and then the samsung is done.
Now for the hitachi, boot into slax with the hitachi hooked up so it goes into mode b (or however you normally do it for yourself) then get into windows load it up with Firmware Toolbox4.6 and dump the firmware. Then restore it back to original and then replace your key with your friends key from his Samsung firmware and flash the key. then do smart hack patcher and select the firmware for it to make and do a diferential flash let it complete then apply a spoof for it to appear as the samsung model he has and flash that and yer done