Wall mount Flodlight Cam

I know Ring claim their Floodlight Cameras are not designed to be mounted under a soffit, but instead only to a wall. Well I was finally going to be able to do a wall mount and was hopeful of a simple install for a change. No such luck. I remove the existing light and realize the junction box isn't round, it is a standard single gage junction box but turned 90 degrees. So the mounting holes in the junction box are the standard 3.25" apart. The problem is that the mounting plate that comes with the camera have studs for mounting the floodlight that are spaced about 3.5" apart. The threaded mounting studs for the light need to be level for the light to be level. And because the studs are in the way, there are no slots/holes available for me to mount the plate to the junction box (see the picture). Any ideas on how to mount this plate so I can mount my floodlight? Thanks.