I am thinking about finally picking up a 3.5 inch wd blue but I am not sure where I can put it in my PC. I got my case, Bitfenix prodigy m, second hand and didn't get any of the accessories for it. The only 3.5 inch mounting points seen to require a rubber grommet, otherwise they would be too big for a screw. How can I get some of these grommets or where else could I mount a hard drive?