I would try to Reformat the hard drive using disk utility which will erase everything currently on it tho so make sure to backup anything you don't want to lose if you kept it on there.
Im pretty sure if you want to just mount it with tape that would be perfectly fine. Had mine apart and even thought about it myself before properly mounting it.
Well this was the second time taking the iMac apart as I had ordered an mSATA drive instead of SATA for the Optical bay swap. Got it apart and back together pretty fast and without issues except for the mounting bracket from the Optical drive doesn't fit that great onto the HD mount to replace it. The kit almost needs to come with a custom fitting mount piece but then again that would just cost more money.
OH!!!! and the kit I bought there was no need whatsoever to take the optical replacement mount apart... it was all in one piece and good to go, just don't forget the little set screw that secure the 2.5" drive into the mount which like others have noted are not in the instructions.
I just replaced with a 250GB SSD... So yes it does support this.
Replaced the 500GB hard drive to a 2TB hard drive, was gonna put a SSD in optical bay as well but ordered a mSATA drive instead of SATA by accident. Overall was pretty easy but very painful trying to reconnect the Display cord. All in all... I've worked on my now 4th apple computer... and 4th computer of all time... and if I can do it you can do it, Make sure your new HARD Drive is the same brand as the one that comes with macbook. I just had to sand down the connection for thermal sensor a little but otherwise it fits without hassle.