ED250

Hi, Newbie question, what type of Mount is everyone using a G+ enclosure with the DNA 250 board. Not seeing much from alpinetech, also for the 12mm fire hole what switch been thinking mitec, But I see people using the Otto. Having a techie do this assembly I do want it to work. Box is type 2 also. Any help on gathering the right parts. Using a Cisco 510 should be enough room for dead center 510. Thank You