Yeah, that would be a good additional note I didn't think of on the cable... I was assuming he has a "newish" system, but you know what happens when you assume sometimes.
Although, even if he wasn't to have an open 3.5" hard drive bay... oh, it wouldn't be the first time I've had a full case and STILL sat an additional drive in a box any ways. Even though it's not the best solution I've both rested them on a foam pad on the floor of the case (ahhh you're not going to want to ever move the system around though
) and I've purchased thin, metal strip brackets from the hardware store and "built" a mount extension off the bottom of the existing drive cage (that was already used up) to "make" room for one more drive.
Where there's a will there's a way man!