I remixed the Fits Adapter for Ford Maverick Cubby (flat bottom) by Clarencws with the Ford Maverick FITS Ball Mount Phone Holder by F13 Bubba to make this cubby insert with a built in swiveling phone mount.

The phone holder fits my iPhone 13 with a case on it, with about 1/8" to spare on the side.

I printed this out of Matterhackers NylonX at 260 with the bed at 70. You can use whatever you want, but PLA will melt in the summer if you live in the south. Pick your own settings that work best with your printer and filament.

Once you have printed the cubby insert and the nut use a flathead screwdriver to spread the nut over the ball. The orientation of the printed nut should have the tightest side toward the cubby. Then use a M3 bolt and nut to close up the slit in the printed nut. Then screw the phone holder on with the printed nut. I used some velcro tape to secure the cubby insert into the cubby.

Good luck!