Yup Done in my computer already. 4 partition with xp, 10, data, hackintosh.
0. goto bios set legacy mode, boot non uefi per install with usb/disc
1. Install xp first in first partition while...

Hi
Just last sunday i upgrade my tripple boot Win7->Win10,Winxp,OSX86
I think you better upgrade win8 instead win7. honest...
save the activation token and key later windows7 if you like to...