I didn't understand the last sentence about the parallel carb rotation.

But to answer your question about throttle setting...
Set your radio and linkage so the carb is all the way open when your throttle stick is all the way up. Make sure the servo isn't trying to push the carb even further as this will strain and drain your servo battery.

You should have a little space in the carb when the throttle stick is all the way closed...this will allow for idle...you don't want the engine to quit when your stick is all the way down.

While the engine is running, adjust your radio End Point Adjustment (EPA) to lower or raise the idle to a satisfactory level.

Your "Kill" swich will then shut then engine off.