PC on the airplane

well, I'm flying to chicago to deliver this piece of new machine I just built. I'm taking the PC on-board, and don't plan to remove any hardware from it, even the HS - especially after talking to many people; I decided that the case will be on it's side most of the time so the heat sink will point up. Are there any precauseions I should take...like leaving the case open for the inspectors to see if my PC is not a bomb, etc. Will the scanning equip erase any data on my hard drive?

No, the x-rays are harmless to the magnetic media and optical drives. Just be sure the guts are easily accesible (i.e. thumb screws) and don't let them make you check it no matter what - otherwise you'll be arriving with fragments that were once a PC.