So, I cut the headband and bent it to a clamp that I covered in red heatshrink tube. I also covered the inside of the speaker body with thin sheet foam, red again to go with the red theme of the Koss headset 
And here it is!
Oculus Rift kosS
Need to route the cables and solder a 3.5mm jack.
Oh, I forgot.
I had to remove the plastic Display/USB chord hook on the left side of the halo. Need to secure the chord with something else…