Coast Guard regulations are rather descriptive concerning full size medal wear, there is not much interpretation involved.
Wear up to five on a row when over six total medals are worn.
Wear Full size medals when wearing these uniforms.
When wearing Full Dress and Dinner Dress uniforms, all authorized medals shall be worn.
Overlap medals if necessary
Rows of more than three large medals may be mounted overlapping with the highest precedence medal inboard showing fully.
See the difference in the configurations below.
No difference between medal and ribbon device configuration.
Wear devices on the medals the same as you would on ribbons.
The previous are the only device regulations that specifically reference full size medals for the rest of the regulations please see the Coast Guard Ribbon Regulations.
As for the rack builder we interpret the regulations concerning full size medals as follows: