Not sure what previous method you're referring to, (Grub?), so I'll mention one I've used previously,
EasyBCD (community edition).
It lets you add/remove entries to the normal Windows bootloader and then you can select which to boot into at startup.
I've used it to boot WIMs, ISOs, and VHDs but it can also do Linux, BSD, and MacOS.
Since it's using the normal Windows start mechanism, (BCD), and not having to install Grub, to remove Linux you'd just remove the entry from the BCD and remove the drive.
It's just an interface to the bcdedit command within Windows.
You could try it by installing Linux on a flash drive and using EasyBCD to set up an entry to boot into it before going the install to an M.2 option.
Otherwise, what you suggest would also work.