Or you can take this riskier approach, since you have Sprite backup, backup everything into a self restoring file (so that even if you have to competely hard reset, you don't have to install anything to restore), then use something like
Tascal Registry Editor to export your registry. (It's free and it worked for me when I did exactly the same thing.) Then copy the resulting .reg file to your PC, use Wordpad or Notepad to edit it. Do a global search/replace for "SD Card" and change to "CF Card" and save the file with a new name. Copy it back to the pda, rerun TRE, import the updated file and soft reset. If it works, congratulations. If it doesn't, restore from Sprite and either try again or use some other approach.
If you want to go more slowly, instead of global search/replace, you can do it one at a time, but it gets pretty boring after a while.
I'm more adventurous, so I took the "go ahead and do it" approach.

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Want to know about GPS? See
GPS 101. Want to know more? See
GPS 201.
We must pay more careful attention, therefore, to what we have heard, so that we do not drift away. Hebrews 2:1 (NIV)