In your picture what you are pointing to with the arrow is indeed what holds the carb in position. It is a tapered jam bolt inserted from the opposite side and it jams aginst a flat on the carb boss.

To resecure it you must loosen the jam bolt by tapping it back after loosening the lock nut several turns and when the carb can be rotated free it is positioned correctly then holding it hard into the engine so the o ring is compressed while that nut is tightened If that jam bolt threads are stripped it will need to be replaced.

Expecting it to 'suck' in is just wishful thinking.

If you are using a 72 Mhz radio system and using a z bend in a metal throttle arm then that is is an exceedingly bad idea and just like lighting a very long fuse on a stick of dynamite under your airplane. I don,t care how many voted to use a z bend, Bad ideas don,t listen to voters anymore than politions do.

If you are using a 2.4 system then its still a bad idea since you are now the chief flight test engineer on vibration induced RF interferance with 2.4 systems.

John