Also got the headunit swapped temporarily until the few other wiring adapters arrive:

For anyone else doing the headunit swap, i needed a 20 pin subaru adapter for the audio and power input, luckily i found one that went straight to the android plug. You also need the 5 pin vehicle information loom to get reverse and parking brake and speed signals. Saw on another post that a 12-6v converter is required to get full function of the multifunction screen back so got that to fit along with the reverse camera wiring when the loom adapter arrives from japan. Currently no compass or fuel consumption challenge screen but no big drama.
I went with the xv aircon controller as well as looked the same as wrx but cost £15 not £100.