Transfer case motor access

[Cylow]

Something broke yesterday and I got the dreaded ABS /Handbrake / 4x4 Combo warning lights. Lots of clunking and juddering in driveline..

Google says it's probably the transfer case motor... as its x drive.. (I have tested on grass and yep.. one wheel spins quite happily when it should be awd)

Anyone know how easy this motor is to replace?
Is it props and case out? Or fix in situ?
Is this motor actuator the one with the plastic gear ?
It's on various bmw's ? But aldo x5 and x3. mine is 2004 x3. Pretty sure general bmw owners will have heard or experienced this at some point.
Ta

[White94RX]

The actuator motor is fairly easy to replace. But it does have to be coded afterwards with the proper BMW software. It's not a real coding, like when replacing a control module, but there's a classification resistor that has to be reset and learned by the transfer case module.