Hi I used a passenger side Cubby Box off a Rover 25, I've and I removed the metal frame removing the three bolts behind the dashboard, never came across the ECU ,and never tackled the framing for steering to accommodate left-hand drive.
Some of the pictures are quite old( if they are still available )however my posting is only a month or two back
(fil 6909) and I have included a couple of pictures here, almost the end result. Message me back if you want some further information I'm pleased with the result although it was quite exacting not quite done yet ,
but I propose to fix from the side edge with two screws into the the small reveal on the airbag aperture