XP Pro on D: Need to move ALL to C:

I had problems with 98SE on C: so installed XP Pro on D:. Continued with all apps and updates on D: and later found many items referring to and trying to use C:. I would like to physically change D: to C: and remove the C drive. However, all registry functions for system and apps files will still be looking for D:\…whatever. Is there a clean way I can do this without re-installing everything? XP migration is no good for this.