I just mounted a Vortex Venom RDS on my Ruger SR22 using the mounting plate from Gallway Precision. Sadly, on my first trip to the range with this I was unable to vertically zero the sight. At full UP adjustment my POI remains about 4-6" low. I can visually detect a very slight upward cant at the front of the adapter plate so I suspect that is contributing to the issue. I've considered taking the plate off to attempt some adjustment but I'd prefer not doing that because it was pretty tough getting it mounted to begin with - very tight fit. I've thought of possibly adding some sort of spacers under the mounting screws at the rear of the optic but I'm not sure that would do what I think it would - don't really know enough about RDS internals. So, any suggestions from folks who might have dealt with this problem (successfully or otherwise) would be appreciated.