30-30 M-Lok Quiver

Hello, this is my first 3D printing design. It is based off of Hybridtheory1331's “Modular Quiver” but adapted to incorporate an o ring and be a one piece design. I recommend to print it in the orientation in the picture but, i don't fully understand all the settings for printing so feel free to adjust it. Once printed you will have to drill out the holes with a 27/64 drill bit to ensure a tight fit. The O-Ring I used is a 3/8 ID, 9/16 OD and 3/32 width.  You also might have to shave the O-Ring with a drill bit once you have placed it in the slot. Also I recommend mounting it so the tip of your bullet will be closer to the O-Ring. If you have any advise it would be greatly appreciated, Thanks.