I have a bit of an unorthodox suggestion.
So there is this guy.
https://soundman.co/
They sell a kit to mount one in your dash.
However, if you contact them you can send them your dash bits where you would like the ipad to sit and they have a fella that goes by the name of Rafa who will do the install and send it back to you.
I have no idea what any of this would cost.
They have a youtube channel (probably not for everyone) that covers a lot of Rafa's installs into various dashes.
Anyway here is a vid of them showing the general idea how to install one yourself if you are so inclined.
Just an idea.
If I did anything ipad I might consider getting one of the kits and installing one myself.