I don't think the trim ring needs to be very tight against the gasket. I aimed for having even spacing in the gap between the trim ring and the body, but not sure how feasible that was. I put the trim ring in place and used a sharpie in the screw hole to mark the spring clip. It was a challenge for me to drill the spring clip with any precision, since it is so flexible and bent under the pressure of the drill bit. I ended up with slightly larger spacing at the bottom of the ring than at the top. It seems solidly in place, though.
Mike
Mike