I had a little trouble finding clear instructions on this, but I got it to work so I just wanted to share the steps with everyone. [Login to see the link] posted this link to some advanced LG settings [Login to see the link]
If you try to install with file manager, it'll tell you the source isn't trusted and the phone won't let you run the install.

Steps:

Download the file from the link above
Plug your LG Classic Flip into your PC
On the Phone open the USB notification and change it to MIDI mode
On the PC open a web browser and go to app.webadb.com
Hit the connect button in the upper left to connect to your device.
Go to "file Manager" on the WebADB site and navigate to Device > storage > self > primary > Download
Click the "Upload" button towards the top of the screen and navigate to your downloads (on the PC) and choose the LGSettings.apk file to upload
Once that file is uploaded, on WebADB click "Interactive Shell"
Type this command cd /storage/self/primary/Download and press Enter.
Then, type this command pm install -r LGSettings.apk

It may take about 30 seconds to run the command, but it'll work!
If you would like to get back the original settings app you can simply type in the following command “pm uninstall com.android.settings“ and restart the phone.