I think you may have issues putting a round can motor in the x4 -- the drive shaft sits directly below the motor. You could probably come up with a way to mount it higher, at the cost of a high CG, and an additional pinion...its doable, but will take some modifying. I'd be interested to see how you manage to do it.
If you want larger pictures, I have them -- the originals are much higher resolution, but quite large.