Remove blur effect from lock screen on High Sierra

I'm on High Sierra 10.13.5. Following these steps to use my unblurred original wallpaper on the initial login screen of my Mac worked perfectly. Now I would like to do the same thing with the lock screen. While at work I have to lock the screen every time I step away from my desk. But I've never liked that my wallpaper is blurred while on the lock screen. I searched and searched but I couldn't find any instructions for getting rid of the blur effect on the lock screen, only for the *login screen*, which, as I've said, I've already done successfully. Does anyone know if it's possible to remove the blur effect from the lock screen wallpaper?