How do i change the CD drive letter assignments?

> new to xp.
> addd new hd, winxp calls it drive E. Being a creature of habit, I
> want it as drive D. Problem is that DVD rom drive is assigned drive
> D. This disk mgmt console seems to let me change the HD assignments
> but not the DVD drive letter.
> So i can move the HD temporarily to, say Z, but how do I change the
> DVD rom drive to the then open assignment of E do I can switch the HD
> to D where I wnat it.
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