WD’s external 3TB drives are compatible with Windows XP straight out of the box. The way that WD circumvents the 2TiB limit is by configuring the USB-SATA bridge firmware to present the mass storage device as having 4KB logical sectors instead of 512-byte LBAs. This effectively increases the capacity limit to 16GiB. The trick is to find an enclosure that is set up for 4KB LBAs.
Wizer’s solution sounds like the easier option, but you need to be certain that your enclosure can see more than 2TiB. Older enclosures may have a 32-bit limit which means that 2TiB will be the maximum capacity when using 512-byte logical sectors.