There are a number of free and fee partition editing utilities out there. By editing, I'm including the ability to [re][assign] drive letters to any and all partitions. While recommending not assigning drive letters to System Reserved, manufacturer's restore/rebuild partition; while +1 with previous poster that the Window OS partition remain C, you can shuffle "the cards" any way you want.
Acronis Disk Manager, MiniTool Partition something, Partition Magic, etc., are just a few of the many 3rd party partition editing utilities. Do not use XP's stuff, not powerful enough.
"Take care of thy backups and thy restores shall take care of thee." -- Ben Franklin revisited.
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Clone or Image often! Backup... -- RockE (WSL)
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