Well, I did a pizza box version of the plenum block off using some 1/16" aluminum plate and Thermo-Tec Mat.
I drilled extra holes in the air intake, and added a Filter Wears sock. I ran the sock down pretty far, then screwed the air intake in place and taped the edge of the sock with thermal tape to seal it up.
This will do until I can bank roll a particulate separator as I am convinced that this is the only way to protect the engine from injesting dust if running in any such environment.
NOTE: I have no clue as to how my photo was posted sideways and that it double posted.