Here is a very important tip when trying to keep the FFG system centered.

To keep it centered you adjust it from the screws that hold it on the rear bulkhead. But what if the rear bulkhead is not sitting perfectly straight.
I've found out that although it is secured with countersunk screws which usually limit the amount of movement allowed, there is still some movement in the rear bulkhead.
In this respect I strongly suggest to loosen a bit the screws that hold the bulkhead on the chassis and twist it left / right to see how much movement there is and where it is best centered. Then fasten the screws tightly.

I also had experienced the same problem where it had more movement on one side and almost no movement to the other.
Because this issue appeared only after I switched from the carbon chassis to the aluminum chassis I was certain that the system was perfectly functional and it was a matter of assembly issue. I just had to locate where I had made an error and it turned out the rear bulkhead was slightly twisted to the right.

Please check yours.