Anyone deal with this rail on their ar556? Bought it was not cheap $94. Told it would fit all including the Ruger. Wrong sorta. First things first very nice rail the bad does not fit over the hand guard ring or bayonet stud. Off by about 1/4-1/2 ". Company states "grind away" or return. It does fit and looks good but the cutouts don't match up and lug is now unusable as a sling mount. Has anyone used a dermal on this rail with good results? I have one but hate to modify it. Again could just leave it alone although it does touch the ring and lug but don't think it will harm anything as is. Just wish it fit right at that cost. Again anyone deal with this rail yet.