Installing Windows 7 on Mac

Good day to you all i have been using the Mac for a very short time and just want some advise. I installed a version of Windows 7 onto my Macbook Pro a few months now using Bootcamp.
I installed a 32 bit version which now recently found out should've been a 64 bit version.
Do i need to change this and if so how easy is it to do?

Thanks in advance,
Paul

There is no upgrade path to go from Windows 7 x 32 bit to Windows 7 x 64 bit. You would have to remove the 32 bit version and install the 64 bit version. In other words, you will have to start over. You may be able to install the 64 bit version over the top of the 32 bit version if there is enough space on your Boot Camp partition to do so. But none of your 32 bit version data will be preserved.

Perhaps in an attempt to save you some troubles, might I ask why you need the 64 bit version of Windows? Unless you need to address more than 4GB of RAM, there are very few reasons to do the upgrade.