Bootcamp partiton for Windows 7 from XP / new or enlarging it possible

Bigger bootcamp partition for Windows 7 over XP possible?

I'm starting the clean install of Windows 7 64x from XP (already have Snow Leopard), but I wanted to increase the size of the partition in Bootcamp for it. My XP partition has 32GB but that partition filled up quickly.
I'd like to use 100GB for the new partition but don't know if it's possible to install the "upgrade version" on Windows 7 on a new partition.
(Maybe it is possible to increase the size of the existing partition?) No clue how the installation software detects that I have Windows XP.

If I use a new partition, will the cheaper upgrade version of Windows 7 detect that the computer has Windows XP already on it and allow the installation to the new and bigger partition? I don't want to start it and have Windows installation tell me I have the wrong version etc.

If someone can give a step-by-step, some advice or experience from doing it, it would super useful!!

(I have a MacPro quad-core 2.8Mhz Intel processor with 8GB RAM)

You can increase the size of your Boot Camp partition with free software from Paragon called "CampTune". Be sure to follow directions as it requires creating a bootable CD and then running the program from the CD.

As to your question regarding the upgrade..... Since you can not upgrade a 32 bit version to a 64 bit version, installing Win 7 64 bit requires a clean install.

What you can do (after increasing the partition) is boot to Windows XP and insert the Win 7 DVD and start the install. The Win 7 install will move everything from Win XP to a separate folder and then install Win 7 64 bit clean.

And yes, the upgrade of Win 7 64 bit will work.

Make sure you have a backup of your Snow Leopard partition and the Windows partition before starting the upgrade.

Regards.