Has anyone used the Z390 FTW motherboard in a Fractal Design Define R6 USB-C (or any R6) case?  I'm wondering specifically about the motherboard's horizontally mounted connectors at the bottom running into the case's power supply shroud.

Yes, there's a grommet at the bottom.  So, I'm not worried about the cables.  I'm worried about the actual connectors having enough room to connect sideways like that without running into the metal of the non-removable power supply shroud.  Since that grommet is right below the USB 1 and 2 headers as well as the front panel connectors (on the bottom-right of the motherboard), those will probably be fine.  But the front panel audio header and the two PWM fan headers at the bottom-middle-left worry me.  It looks like the interior of the case is about 13 inches long (top to bottom), and the motherboard is theoretically 12 inches long (top to bottom in that orientation).  I just don't know how the fit will be in reality.
 
EDIT:  Thinking about this some more, I think it'll be fine.  I never use the front-panel audio, so even if the connector doesn't fit, that's not a problem.  I can't imagine plugs for fans not fitting in that space.  And, as to the 6-pin (?) ATX power connector that I forgot about at the far bottom-left, there's another grommet on that side that'll ensure it should fit.