Whiteline rear sway bar kit

[JARVIS]

So I installed the kit and had some issues with the u clamps tightening all the way. I ended up having to replace them and installed new ones as they stripped due to movement. It seems to be holding up prior to shipping it but still worried it may strip again over time or cause damage to the axle. Is there another clamp I could use instead of c clamps to connect it better to the axle? Thanks