OK, a little background for those who are non-iDrive...
AVIN USA and a-carnavi.com make this version for the e90 series in both Left-Hand and Right-Hand drive versions....
https://avinusa.com/10-25-bmw-3-seri...on-system.html
This system turns the standard Professional head-unit into an iDrive equivalent by adding in a T cable loom and then modifying the dash top for the screen. The Left-Hand version has been on the market for a couple of years now with the Right-Hand version coming out earlier this year. It is an identical set up connection-wise to the e89 so all you would need is a mount.
Now this does run a 10" screen and the space for the dash-top cubby/ iDrive pop up screen would be for an 8" screen of which they do use for some other configurations, so would be best suited to the 8" so as to not need to alter the dash for either iDrive cars and non iDrive cars.
It's a very neat system indeed and adds so much more to what you can achieve over the standard iDrive package