HA! Now that you’ve dubbed it , “the spinning bash guard of doom”, I have my heart doubly set on it. Whereas before, I was going to grind the teeth off of it, I might make them even more scary looking now. 
I think you may have something about flipping the internal disc hub and using with a right-side KH mount, and then also using a disc on the crank as a guard. I’ll try that and see if the caliper will line up.
Hmmm … a quick look at the caliper confirms Eric’s last posts (which I didn’t read until now) - caliper will not line up on the right ride as it is asymmetrical (even after shaking it).
Oh well … back to the bash guard of doom … BWAHAHAHAHA!
Unicycle Spinning Disc Bashguard v2.2
So, as promised earlier, I have refined my SPinning Uni Disc BAshGuard (SPUDBAG); taking into consideration the variety of reactions to the 1st prototype.
So - for you safety oriented types, I have ground off the teeth and made a “safety model”: The SPUDBAG-BB “Big Baby” model 
Here are a few mock-up pics showing front a and side views which should clarify some of the questions about ankle clearance and q factor.
These were taken using a KH26 Frame, KH Moment Hub, and KH Spirit 125/150 cranks. The disc is 180mm - notice the guard is slightly smaller than the disc ( it is slightly larger than a 160mm disc). Caliper is a Shimano hydraulic SH-M486.
Note - I messed up in my earlier post - disc shown was a 160mm disc, not a 180mm.
Spudbag-dd
… and I also built a bashguard that truly lives up to the “Spinning BashGuard of Doom” title: The SPUDBAG-AD (“Amputator of Doom”)
The SPUDBAG-AD model comes complete with tempered steel plate and carbide teeth. Capable of destroying any plant, animal or mineral that even thinks about bending your disc!
Adopt this technology at your own risk … 
Failed Prototype for Frame Mounted Internal Disc Bash Guard
Failed Prototype for Frame Mounted Internal Disc Bash Guard:
Easy to build but not stiff enough where it mounts to the frame.
I am showing this so others might learn/improve on it.
I came up with an idea for a frame mounted bash guard that was easy and cheap to make from a length of flat aluminum from the hardware store.
It mounts (on a nimbus) into the narrow gap between the bottom bearing cap and the frame where the bolts go through.
In the end the mounting was not stiff enough to make this design work. the aluminum strip was too flexible and easily touched the disc if side pressure was applied. May be this design can be improved to work.
How to build for 180mm Disc:
Materials: 1 inch / 25mm wide flat aluminum strip (670mm length min)
at 70mm down the aluminum strip, bend the strip roughly to a right angle
Bend aluminum to wrap around 1/2 of the circumference of the brake disc
Bend at a right angle so it lines up with the 70 mm end of the strip.
Line up the the bearing cap and cut it so it will overlap the bolt holes but not the bearing (both straight sections should be about 70mm).
Drill holes through the aluminum that match the bolt holes in the bearing cap
Cut 2 120mm sections of aluminum. Bend them to overlap the main aluminum piece.
Drill holes in the main piece and 120mm sections.
Attach the 2 sections to the main piece with bolts and nuts.
Note: Pictures of mounted guard are over a 160mm disc
