http://pcpartpicker.com/p/MVFCNG

comes in around $1020 (you're not gonna send them rebates in)

installing Windows is pretty simple
just make a bootable USB of Windows 10 on another computer and have your key ready

have only the SSD plugged in when you first boot and you're in the bios setting up your drive. when you restart have your bootable usb in and it should start your installation

after its all done, you can turn off the machine, plug in your HDD, turn it on, check and make sure it shows up in the BIOS, enable it in windows and you're good.

https://www.youtube.com/watch?v=xzr16pxybnI
old but still works https://www.youtube.com/watch?v=qMo8krAJd5Q