We had 2 disks stacked in a server here at the office, they heated so much one of them eventually died and we lost most of what was there. Fortunately we had everything backed up. Take a look at places where you would not usually put a hard drive: the bottom of the case, over the power supply, under the floppy drive, etc. and see if you can put your disk there, maybe with some velcro or other kind of attachment. I've had a server with a disk attached with velcro, and worked fine for years. You could also use those plastic thingys, they are quite strong too. Just make sure the disk doesn't move at all.