Mine is a newer model that was also missing the motor cover. I made a wooden box that holds a slide in 12x12 furnace filter that serves as the air intake for the DC. Not to filter the incoming air, but to keep stuff from getting thrown out. Close off the bottom of the base, the air gaps between the top and the base and cover the blade tilt slot. My motor never gets warm and the DC works great. No dust settles on the motor since the air is drawn in over it. I can cut MDF inside a finished house and not get a spec of dust on anything with a 3hp DC close by. There is an overarm pickup too.

At first I just used blue tape over the tilt slot, but switched to magnetic sheets of synthetic rubber to make it easy to change.