Flip your ionvac right-side up and tilt it upwards at a 45 degree angle.

Use a Jimmy or prying tool to wedge the sharp end through the bottom crevice (below the sensors).

Continue prying the outside rim of your ionvac open. You will feel the top shell (frame or cover) loosen.

Caution: Resist the urge to tear the top shell open until the entire rim has been loosened.