I in fact tried that, on a recent system with an Intel Core i5-2500 and an ASUS P8H67-V (Intel H67 chipset) motherboard with ASUS EFI BIOS.
If a GPT existed, window 7 refused to install on a system with a GPT (instead of an MBR).
On the other hand, if windows 7 is brought to install in UEFI mode, then it creates a partition table of the kind ‘gpt_sync_mbr’
instead of a plain GPT partition table, see
https://forums.opensuse.org/english/get-technical-help-here/install-boot-login/475347-error-occurred-while-installing-grub-during-os-11-4-installation-error-25-asus-efi-bios-4.html#post2463672
I don’t see how windows 7 64 installs fine on an UEFI system.
But in the end this is an openSUSE instead of a windows forum.
And as long as I have tried to, there ever had been severe problems plugging or unplugging hard disks under openSUSE,
as long as these haven’t been USB hard disks.