That steering is a good idea, I've actualy worked a similar idea on my rig but found that without the ckrc high steer knuckled the shocks are in the way. I never finished working that idea due to a busy schedule. If you look at tha xr10 you will see that the steering on it Is built just like that, only exception is that the servo still mounts forwards and attaches to the front of the knuckle.
i was curious about the ckrc BTA kit. it seems like that kit would mimic the stock steering setup, just swap it to the back of the axle. it looks like if you pull the shocks inside the lower axle mounting tabs (where they would need to be to prevent the tire from rubbing them in order to maximize steering angle) the ckrc drag link would also hit the shocks. anyone out there running the ckrc BTA mod?
by adding spacers between the knuckles and the drag link on my i get the equivalent height to the high steer knuckles from ckrc but it doesn't help in the shock/links clearance.
you are correct that what i'm trying to do is very similar to the XR10. the only real difference would be i would keep the servo linkage BTA instead of connecting to the steering knuckle in the front.