ORIGINAL: J_R
Get a metric allen wrench that fits the throttle arm. Move it 180 degrees as in the pic. You should then be able to use a z-bend.
OK, but how are you going to connect and disconnect a z-bend if the engine is cowled in such as this? It will work if you use an EZ connector at the servo end so you can pull the whole pushrod (maybe), but not if you use a real connector. EZ connectors are bad news and I don't use them anywhere. In the case of this aircraft, the rear of the engine has to be pulled out first, so the wire has to be severely bent before the engine is out far enough to disconnect the Z-bend.