Here's another thought. Use Spiro-locks, as the high-tech race car engine builders do.
There are considerable forces acting on the circlips. There is thrust, as well as the impact of the piston changing direction completely many hundreds of times a minute.
This is why regular circlip positioning on the gudgeon/wrist pin is crucial, to reduce the impact forces on the circlip, that make it constantly flex.
Many engine assemblers state they will only open and close a circlip once before discarding it.
Thrust on circlips comes from the impact of combustion on the piston, and also from the misalignment of conrods. Excessive crankshaft end float and poor cylinder-to-crankshaft alignment can create conrod misalignment and gudgeon/wrist pin side thrust.
Spiro-locks reduce the possibility of circlip breakage to virtually nil, and I'm surprised that Jabiru aren't using high-tech racing engine technology such as this.