The engine and gearbox does come out in one unit, I have done it myself. That's how it went in at the factory.
Totally correct Lee.
I bought our M3W in 2018.
Chassis paint finish was poor, I have the Hybrid Chassis.
So I took the engine and box out together. Repainted the chassis.
You just need the car high enough to get some tilt on the gearbox end.
Went in dead easy all together too, saved all the faff with long extensions on the bellhousing bolts.
So YOU CAN take the engine and box out as one item.
Ian.