Just to make sure, remove the center screw holding the horn on the servos. Turn on the radio and receiver to activate them. Turn the throttle trim all the way down and center the steering trim. Reattach the control horns while the carb is closed, and the steering wheels are centered.
Other than the tweaks mentioned above, you'll now be good to go.
All the way down as in set at neutral (center). This will allow you to adjust your idle higher/lower as needed when running your car to temporarily compensate for weather/cold engine etc. Trim settings shouldn't be used for long-term adjustments, adjust your linkages for that. Your engine will thank you
Throttle trim all the way down. That's the only way you can properly set the idle and not stall the engine when you brake. The trim is only turned up to make it a little easier to start cold, and for warming it up.