Hi there crblakely,
It would be nice if you could provide some more information. So your system works fine(OS installed on the SSD) except for the HDD which disappeared right?
If this is the case, you will need to change the port of the drive as well as switch the cables. After that you can go to Disk Management and see whether the drive is recognized over there and whether it has a letter assigned or requires some kind of action(initialization, format, etc.)