The guide says :  The partition scheme and target system type set as MBR partition Scheme for BIOS or UEFI Computers by default and this can be used in most cases. In the rare case where you need to install on a 3 TB or larger drive with a SecureBoot/UEFI BIOS select GPT partition scheme for UEFI computer (I have not tested this). So, if I'm not gonna install Windows 7 on a 3 tb drive, it will be best to disable secure boot and UEFI to legacy ? Or do I only have to disable secure boot, but keep the UEFI setting ?  Reason I ask is that other Windows 7 installation guides says you have to disable these two settings, but in the guide you sendt me it seems like the only thing I need to change may be the secure boot setting. Or maybe not ? 
Have an DELL XPS 8700 with the following wireless and bluetooth chipset/card : Intel Wireless Bluetooth 4.0 + HS Adapter Intel Dual Band Wireless - AC 7260 Is there drivers for Windows 7 64-bit for this chipset ? Reason I asked was when I tried to get DELL to install Windows 7 Pro instead of Windows 8.1 on my machine, their excuse was that there weren't any drivers for these 2 items in Windows 7. I don't quite believe them. Have someone here "converted" from Windows 8.1 (not pro) to Windows 7 and you have the chipset mentioned here ?  
Is there Windows 7 drivers for this wireless and bluetooth device ?