Here is a short but sweet post on how to change the drive letter of a partition. Despite using my best Google skills I couldn’t find an example that was doing it for me. I rolled up my sleeves and just figured it out on my own. I hope this helps someone out there.

Set-Partition -DiskNumber 4 -PartitionNumber 1 -NewDriveLetter X

As long as you know the DiskNumber and PartitionNumber this will immediately change the drive letter of the partition you specify.

Source: DZone