I bought a red dot and it won't fit on the rail with the iron sights. I want to use the red dot, cowitnessed with the front iron sight. I also want to have a popup sight for the rear if my battery dies in my red dot. Has anyone bought one that works on the stock rail and lines up with the front sight? I have looked and found a few different heights so I am not sure what size to buy. Sorry for the page long post and I searched but didn't find any info. Thanks.