Get an ATM from convertible - it comes in a black case and goes into trunk, just like TCB or TCU.
Like this one
https://www.ebay.com/itm/153169841189/
Just make sure it comes from a junkyard, not a repair shop - there was an issue with iStep upgrade bricking early ATMs and you may end up buying an ATM bricked by such an upgrade.
Fun trivia: ATMs run Android.