Is there a rack kit to mount two RME half-rack units side-by-side in a single rack space without using one of those universal rack shelves? I've seen kits by other manufacturers that allow the two units to be joined in the middle somehow, and then there are standard rack ears on the left and right as normal. I've got a Multiface and an ADI-2 that I want to do this with. Also, why bother equipping the single, half-rack units with rack ears? Is there such a thing as a half-rack sized case (with rack rails)?