I have a CMMG Quebec-A (dedicated .22lr upper on a multi-caliber marked lower) and I want to mount a red dot on it. The red dot I have is a Millett RD00006. I have A2 style sites (cheap UTG) and a riser for the red dot so that I can set it up to co-witness. Problem is that the riser rail is longer than the the rail that is left on my receiver. Could I mount the red dot at an angle? Are there drawbacks? Please don't respond with get a primary arms, eotech, insert brand x here. I have the equipment that I have and it is a .22lr plinking toy. Once I get a 5.56 upper, then I will come back for suggestions for both BUIS and optics. Thanks!