Polaris65 connection too small??

I have a Polaris65 which should connect to my water intake/light on the side of the pool. Since it is a light, I was told to buy a connector to put over it (to convert it to thread to my P65). My problem is that the connector is too small to fit over the existing light. Are there larger ones that I can buy? Or do I need to replace the light/intake water hole entirely?

Thanks ! I've inherited this pool and am learning sloooowwwly!
H2oNewbie