^^^ Yep. You can also buy trays designed for such large-capacity hard drives. The location of the standard screw mounting holes changed at some point, so the drive trays the Mac Pros shipped with will not hold large-capacity drives.
The new trays are not expensive and can be found from a handful of vendors, including Other World Computing. I do not recommend trying to mount a large drive without such a tray. Using tape isn't that secure (I've done this, too). You can destroy your Mac Pro's logic board and it's not worth that kind of risk to save $20 on a tray.