Windows XP x86 to x64

I am very shortly going to be upgrading my OS from the 32-bit version of XP to the x64 version. I really don't want Vista, and I have all the drivers I would need for XP x64, but that's really beside the point.

I know that it isn't possible to do an upgrade installation, I have to nuke my current OS in order to run x64. I keep my OS on my C drive, and all of my other applications on various other internal drives. Installing x64 will take out my registry, and therefore will cause x64 to think that none of my current applications really are installed.

I'm sure most, if not all, of my applications would run fine that way, but I'd rather bring all of that information along with me to x64. Would exporting my registry from the 32-bit XP and importing that into x64 create a train wreck out of x64, or would it go at least somewhat smoothly?